The Sydney Mint opened in 1855 as a branch of the Royal Mint London, its function to produce gold sovereigns and half sovereigns. The mint was closed in 1926 striking its last gold sovereign in that year, the irony that a mint could be unprofitable.

Three monarchs reigned between 1855 and 1926, Queen Victoria (1837 - 1901), King Edward VII (1902 - 1910) and George V (1911 - 1936). The Queen Victoria era was represented by five portraits, Sydney Mint Type 1 (1855 - 1856), Sydney Mint Type II (1857 - 1870), Young Head (1871 - 1887), Jubilee (1887 - 1893), Veiled Head (1893 - 1901) and George V era (1911 - 1926).

1853 - 1870
To come

1871 -1887
The Sydney Mint produced sovereigns and half sovereigns featuring the Young Head portrait between 1871 and 1887. 

To come

1887 - 1893
To come 

1893 - 1901
To come 

1901 - 1910
To come 

1911 - 1926
To come .. 

Australia’s Proof Sovereigns and Proof Half Sovereigns are coins that were quite literally, fit for royalty. They are powerfully irresistible. And they are respected for the history they represent. They are sought after, the world over, for their exclusivity.

You don't buy a piece of proof gold and then put it aside. You savour the moment and you take in its glory, and you show it around to family and friends for they are exclusive and they are beautiful.  

Today's collectors are showing a marked preference for pairs if, and when, they are available. So not one coin, but two, the Proof Sovereign and the Proof Half Sovereign together. The current sentiment is that a pair is the mint's complete story, the total narrative. 

And this principle is being consistently taken up and reflected in Coinworks sales. The 1901 Perth Mint Proofs sold as a pair for $525,000, the purchaser commenting that he would not have bought an individual coin because it was not the complete story. The same views were expressed by the purchaser of the 1871 Sydney Mint Proof Sovereign and Half Sovereign. And in March 2026, a Proof 1896 Sovereign was acquired by a collector that already held the 1896 Proof Half Sovereign.

The pursuit of completion is also being shown in other areas of the market. The Complete Kookaburra Collection sold within a few hours of its release, the key here is that it was complete. A date set of kookaburra pennies, complete for each of the dates in which the coins were struck, is also today a strong collector favourite. In February 2026, a Coinworks client completed a 'mint' set of Holey Dollars: four Holey Dollars representing the mints Madrid, Lima, Potosi and Mexico. 

Complete sets are naturally heirloom-worthy. They’re easier to pass down, easier to explain, and more likely to retain their identity over generations. Families understand the concept of the full set instantly.

Let's also be clear. There is a significant amount of collector/investment dollars available globally. And buyers with significant financial resources are looking to spend their money on an item that has substance. And pairs or sets have more substance than an individual coin.

Coinworks is also making this offer to clients who are considering a pair of proofs. Take the first coin and we will guarantee to hold the second coin, and hold the price, for six months to facilitate a purchase of the pair. 

Royal approval was given in 1853 for the establishment of the Sydney Mint. Colonial coining operations officially began in 1855, the Royal Mint London producing the dies for Australia's first sovereign and first half sovereign.

Australia's first sovereign was struck on 23 June 1855, the half sovereign a few months later. The coins were struck with a British styled portrait of Queen Victoria and a strikingly Australian reverse proclaiming the word 'Australia' and the issuing authority of the 'Sydney Mint'. The obverse and reverse designs were used again in 1856.

In 1857, the obverse of the Sydney Mint coins was amended by British engraver L. C. Wyon to incorporate a more Australian flavour into the design, Queen Victoria sporting a sprig of Australia’s native plant, the banksia, in her hair.

The first design used in 1855 and 1856 is referred to as the Type I design, the amended, second design the Type II.  

The styles, Type I and Type II, are collectively referred to as the ‘Sydney Mint’ design and lasted until 1870. Major revisions occurred in 1871 to both the obverse and the reverse to eradicate the Australian flavour from our gold coinage. The words Sydney Mint were eliminated, replaced by a discrete 'S' for Sydney mint mark. The word 'Australia' was also eliminated. And the portrait was replaced with a neo-classical style popular in Britain, the monarch featuring two bands of ribbons in her hair instead of the banksia 

In 1853, the Royal Mint London tested the dies, and recorded the designs, by striking frosted proofs of the proposed sovereign and half sovereign coinage.

Four pairs were produced and they are all accounted for. They are 'Coins of Record' in the truest sense. The  Royal Mint Collection holds two 1853 proof pairs. The British Museum holds another pair, acquired from the Royal Mint in 1854. The remaining pair is held by a private US collector and was first offered in 1981 by Spink Auctions Australia, eventually finding its way into the Quartermaster Collection, in 1992. The last recorded sale of the 1853 proofs was in New York in January 2026 for A$655,000. Given that the 1853 Proof Half Sovereign is marred with imperfections, this is a solid result. 

Proofs were also struck at the Royal Mint London in 1855, 1856, 1857, 1866 and 1870. The close connection between the mint in London and leading British collectors has meant that many, if not most of the proofs, made their way into private hands. 

The 1855 Proof Sovereign is not held in any public institutions, worldwide.

A pair of 1855 Proof Sovereign and 1855 Proof Half Sovereign appeared in the Murdoch Collection (Lot 615) and appears to have become part of the Nobleman Collection by Sothebys in 1922 as Lot 699. At some point in time, post-Nobleman, the pair was broken up. We know that Max Stern Melbourne handled the proof sovereign in 1969 (where it was offered privately to Barrie Winsor). The next sighting was in July 1985, sold by Spink Australia for $32,000, the coin's first and only appearance at an Australian Auction. The coin was acquired from Barrie Winsor in 2000 and is now held (with the Half Sovereign) by a Coinworks client. 

A second privately held 1855 Proof Sovereign surfaced in 1999 in the UK held by the Strauss family and was sold to Barrie Winsor by private treaty when it eventually became part of the Quartermaster Collection. The coin was sold By Heritage Auctions in the US on May 5, 2022 (Lot xxx), and is still located overseas.

A third 1855 Proof Sovereign was offered by Kunker Auctions Number 316 (Lot 869) in January 2019, the coin noted as coming from the Pretoria Mint. The coin is also held by an overseas collector. 

Conclusion. The 1855 Proof Sovereign is known by three privately held examples, two of which are held by overseas collectors. 

The Museum of Victoria holds one 1855 Proof Half Sovereign acquired from A H Baldwin, London in 1929. The British Museum also, holds an example, acquired in 1935 as part of the Clarke-Thornhill bequest. The interesting point that the coins currently held in institutions were acquired commercially and not transferred (gratis) within the minting system. The Royal Mint London did not seek to retain any examples but they were made available to collectors.

An 1855 Proof Half Sovereign was held in the John G Murdoch Collection, sold Sothebys London 1903 (Lot 615). The next recorded owner was Virgil M. Brand (most likely acquired from the Nobleman collection but not cited) then to Captain Vivien Hewitt, John Ahbe and Spink Australia Sale 6, Noble Numismatics Sale 62 (Lot 983). 

A second privately held 1855 Proof Half Sovereign surfaced in 1999 in the UK held by the Strauss family and was sold to Barrie Winsor by private treaty when it eventually became part of the Quartermaster Collection. The coin was sold in the US in January 2026 by St James Auctions, where it still resides.

A third 1855 Proof Half Sovereign was offered at auction in March 1985. The coin had been held as a pocket piece and was described as 'Good Fine', selling for $16,200 on an estimate of $20,000.

Conclusion. The 1855 Proof Half Sovereign is known by three privately held examples, one of which is held overseas. Two are held in Australia, one of which has circulated. 

The 1856 Proof Sovereign and 1856 Proof Half Sovereign are not held in any public institutions, worldwide.

Murdoch held an 1856 proof pair (lot 616), Nobleman only the Proof 1856 Half Sovereign (lot 700).

Today, two examples of the 1856 Proof Sovereign are privately held, the first ex Murdoch, King Farouk Egypt, Spink Auctions Australia 1978 (Lot 541) and November 1981 (Lot 985). Its final auction appearance was at Morton & Eden London on 11 December 2003 (Lot 521) where it was acquired by Barrie Winsor and sold to the Quartermaster Collection. The coin most recently exchanged hands at Heritage Auctions (US) on 5 May 2022 (Lot ) where it sold for xxxx. And where it currently resides. 

The second example was offered in Monaco in December 2016 by Editions V Gadoury Auctions 

Three examples of the 1856 Proof Half Sovereign are known today. The Murdoch example (Lot 616) followed a similar path the sovereign, King Farouk Egypt, Spink Auctions Australia November 1981 (Lot 985). Its final auction appearance was at Morton & Eden London on 11 December 2003 (Lot 522) where it was acquired by Barrie Winsor and sold to the Quartermaster Collection. the coin most recently exchanged hands in January 2026 at St James Auctions (US) where it sold for xxxx.

A second example was offered at Spink Auctions in July 1987 (Lot 1879) and November 1999 (Lot 1420). A third example surfaced in 2005 (Lot 1229) ex Pretoria Mint South Africa.

The Royal Mint holds an 1857 proof pair. The Murdoch Collection held two pairs of the 1857 proofs (Lot 617 and 618), the first pair purchased from the Brice Collection (Lot 308) thence to the Montagu Collection 1896 - 1897 (Lot 310). The second pair came from the L C Wyon Collection, Wyon a British engraver most notable for his work on the 1855 reverse and 1857 obverse portrait on Australia's Sydney Mint coinage. 

Today, three examples of each of the 1857 Proof Sovereign and 1857 Proof Half Sovereign are believed privately held. 

The above 1857 proofs, Brice, Montagu, Wyon, Murdoch were struck at the Royal Mint London and feature a plain edge. Milled edge examples of the 1857 Proof Sovereign also exist. Three are known, one of which is held in private hands. The remaining two coins are held in Government institutions, the Museum of Victoria (donated by Dr William Howatt in 1926, acquired from the Sydney Mint). And the Biblioteque Nationale de France in Paris. The coins have a richness and strength that the Royal Mint strikes simply do not have and were believed minted at the Sydney Mint, circa 1883 (when the Sydney Mint received the dies from the Royal Mint). Or on closure of the Sydney Mint when a number of presentation strikes were executed. 

 Two pairs of the 1866 proofs appeared in England in the early 1970s. It appears probable that these two pairs are the same coins recorded as being cleaned by the Royal Mint for the colonial office in 1879, proofs struck at London for exhibition purposes. 

The year 1870 was the very last time the Sydney Mint design was used on Australia's gold coins. An important year, only one example is known of the 1870 Sydney Mint Proof Sovereign. 

There are no recorded examples in public institutions, museums and Government archives, both in Australia and overseas. And this includes the Museum of Victoria, the Royal Australian Mint in Canberra, the British Museum and the Royal Mint London, all of which have extensive holdings of Australia’s heritage coins. The Royal Mint still has the proof dies. And a pair of strikings in tin of the obverse and reverse bearing the legend MODEL/E. They are held at the Royal Mint, Wales.

During a posting in London in the 1970s Barrie Winsor established a provenance on the 1870 Proof Sovereign that dated back to 1873. He also recalls being offered the coin in 1976 by Judith Spiers of Spink for £4000. (Sadly he recalls, he had to decline the offer.)

The 1870 Proof Sovereign was first offered by Sothebys London 26 May 1873 in the sale of the John Brodribb Bergne Collection. Sighted again at Sotheby, Wilkinson & Hodge 7 April 1881 in the sale of the J Haliburton Young Collection, thence to the Montagu Collection sold Sotheby Wilkinson & Hodge 1896 & 1897 (Lot 309). The chain continues to the John Gloag Murdoch Collection sold Sotheby 26 July 1903 (Lot 619), then to Captain Vivian Hewitt Spink 1967, Baldwin Collection, London, Spink Australia November 1978 (Lot 564), Spink Australia July1981 (Lot 989) and Spink Australia July 1988 (Lot 2304). A truly remarkable coin, quite possibly the greatest example of proof coining of any date. With a provenance to match! 

The Sydney Mint design has the greatest international appeal of all our sovereign designs, the only one to feature the word Australia. An example of the 1855 Proof Half Sovereign and 1856 Proof Half Sovereign sold in January 2026 in New York, the 1855 fetching $220,000 ($242,000 with GST), the 1856 Proof Half Sovereign $182,000 ($200,000 with GST).

The coins had been thrown to the wolves by the Auction House, letting the market decide a market price, the estimates $50,000 and $20,000 respectively.

The coins produced at the Sydney Mint during the Young Head era featured new obverse and reverse designs. The sprig of banksia in the queen's hair was replaced with bands of ribbon presenting a more traditional regal style. And two new reverse designs were introduced, that of St George and the Dragon by Benedetto Pistrucci and the Shield design of J. B. Merlen. The Shield reverse was the only design used on Australia's half sovereigns during the Young Head era.

The Sydney Mint struck its first Coin of Record in 1871. (Prior to this all 'Sydney Mint' proofs were struck at the Royal Mint London.) 

The Royal Mint London produced the dies for the '1871' strike. That the Sydney Mint held the dies (as indicated in their records) and, the lack of examples in official British Collections, suggests that the proofs of 1871 were the first set to be struck in Australia, and the first striking of imperial proof gold coins outside Britain. Important indeed. A keen numismatic eye will also acknowledge distinct differences between Royal Mint and Sydney Mint strikes.   

The proofs of 1871 appeared at Sothebys auction, in London in 1888, in the sale of the Marsham Collection. An 1871 St George (milled edge) and an 1871 Shield (plain edge) Proof Sovereign were offered as lots 832 and 833 respectively. The 1871 Proof Half Sovereign (milled edge) was offered as lot 834. (Prices realised were £5 12s 6d, £9 10s and £4 10s respectively. Note the price of the plain edge shield example.)

The milled edge St George example passed through the hands of Murdoch, sold 1903 Sotheby (Lot 620), Huth, sold Sotheby 1927, (Lot 627) and Whetmore, sold Glendinings 1943, (Lot 192). That the plain edge shield sovereign sold at the Marsham sale in 1888, but has never been sighted since, suggests that it was acquired by an institution. The 1871 Proof Half Sovereign was offered in the Whetmore Collection sold Glendinings 1943 (lot 201). 

The 1871 St George Proof Sovereign and 1871 Shield Half Sovereign were offered first offered at an Australian auction by Spink Auctions Australia in 1978 (Lot 599 & Lot 650), in November 1981 (Lot 991 & Lot 999), and again in July 1988 (Lot 2305 & Lot 2306). They were sold by Coinworks in 2024 to a Canberra collector. 

No other 1871 proofs have ever been sighted.

It is noted throughout the Sydney Mint's history that it experimented with both milled and plain edge. The Melbourne Mint's plain edge strikings were kept within minting circles. Both plain edge and milled edge examples of Sydney Mint proofs are noted in collector's hands.

Barrie Winsor records in his notes the production of a specimen sovereign in 1879. Unique. He also notes that it is impaired.

The next proof issue to be struck by the Sydney Mint occurred in 1880, no doubt for the Melbourne International Exhibition, a significant event in the history of colonial Australia. It was the first official World's Fair in the Southern Hemisphere and took place from October 1 to April 30, 1880. 

The Dangar Collection sold by Glendinings London in 1954 offered an 1880 Shield Proof Sovereign (milled edge) as lot 221 and a St George Proof Sovereign (plain edge) as lot 222. One example of the 1880 shield sovereign (milled) has been offered by Spink Auctions Australia in November 1978 (Lot 657), November 1981 (Lot 992) and again in July 1988 (Lot 2307). The Dangar example? Unconfirmed. Spink also offered a St George sovereign (milled), in November 1986 (Lot 717), the coin impaired and was passed in.

The Dangar Collection sold by Glendinings London in 1954 offered a milled edge 1880 Proof Half Sovereign as lot 225. An 1880 Proof Half Sovereign was offered in 1974 by Glendinings and fetched £520 (Lot 22). A Proof 1880 Half Sovereign was offered by Spink Auctions Australia in 1978 (Lot 657), 1981 (Lot 1000) and 1983 (Lot 525). A second example was offered in 1988 (Lot 2308). Notation linking coins offered in Spink Auctions to Glendinings is lacking. Our estimate on the number of examples available to collectors in today's market is two, perhaps three.

A pair of 1883 Proof Sovereign and Half sovereign was sold by Barrie Winsor through M. R. Roberts in 1985 and is the only known proofs of this year.  

A Proof 1886 Sovereign is reported but has never been confirmed. 

No Young Head proofs were struck in 1887.

As a summary, the Young Head era of the Sydney Mint spans 1872 to 1887.

There are extremely limited options for collectors of proofs in the Young Head era: 1871, 1880 and 1883. The 1871 pair is unique and is now in a long-term holding. The 1883 pair is also unique. The 1880 proofs are extremely rare and elusive. A sovereign struck to a specimen finish in 1879 is noted. 

It is a privilege to be offered a Sydney Mint Young Head proof.

Victoria became Queen of the British Empire on 20 June 1837, and her golden jubilee celebrated fifty years to the day, on 20 June 1887.

A new sovereign portrait was designed by (later Sir) Joseph Edgar Boehm to replace the Young Head portrait. The new design drew inordinate criticism for Victoria’s apparent scowling look and the precarious balancing of her crown. The design only lasted six years.

The year 1887 also saw the dropping of the Shield reverse on Australia's sovereigns. All Jubilee Head Proof Sovereigns were struck with only the St George and the Dragon reverse. The Shield reverse was however maintained on the half sovereign.

The Sydney Mint struck proofs in the first year of the Jubilee era, '1887' And the last, '1893'.

To commemorate Queen Victoria's jubilee, the Royal Mint London produced gold coins in denominations of Five Pounds, Two Pounds, Sovereigns and Half Sovereigns in both proof and circulating issues. 

Emulating the Royal Mint, the Sydney Mint struck two four-coin Proof Sets, one of which was obtained by John G Murdoch (Lots 613, 614 and 625). The other set was obtained by Sydney politician, Henry Dangar (Lots 226, 227 and 228). A further ten Two Pounds 1887 proofs were struck and were progressively sold at a premium of 25%.

The Murdoch Collection also held an additional 1887 milled edge proof sovereign and half sovereign pair (Lot 626). The Sydney Mint also produced a plain edge pair, its destination the Murdoch Collection (Lot 627). 

An 1887 Proof Sovereign was offered by Glendinings in 1939 in the sale of the Hamilton Smith-Briggs Collection (Lot 257). Most likely from the Murdoch Collection. The Quartermaster Collection held a complete 1887 Proof Set Five Pounds, Two Pounds, Sovereign and Half Sovereign, the four pieces confirmed ex Murdoch Collection.

Spink Auctions Australia has offered examples of the milled 1887 Proof Sovereign (in 1978, 1996 and 1998, the latter impaired) and one of the plain edge in 1993. Most likely ex Murdoch, but unconfirmed. 

The company has never offered an 1887 Jubilee Proof Half Sovereign.

Plain edge 1887 Proof Sovereign and Proof Half Sovereign are held in the Museum of Victoria, a bequest from Dr William Howat, who purchased them from the Sydney Mint in their closing-down sale for 30 shillings and fifteen shillings respectively and donated to the museum in 1926.

The dies for the sovereign and half sovereign were transferred to the Melbourne Mint and on its closure to the Royal Australian Mint Canberra. 

Two pairs of the milled edge Jubilee 1893 Proof Sovereign and Proof Half Sovereign were held by the Murdoch Collection and offered by Sotheby Wilkinson & Hodge as lot 632, 634 and 635, one of the pairs split into two lots. 

An 1893 Jubilee Sovereign (milled edge) was offered at Spink Auction November 1985, most likely ex Murdoch.

An 1893 Proof Half Sovereign was offered by Sothebys in 1927 in the sale of the Huth Collection (lot 630), again most likely ex Murdoch. The 1893 Jubilee Proof Half Sovereign has never been sighted at an Australian auction.

The plain edge examples in the Museum of Victoria are from the Sydney Mint, the coin purchased by Dr William Howatt for 30s and 15s respectively and donated to the Victorian Collection in 1926.

As a summary, the Jubilee era spans 1887 to 1893 and during those seven years the Sydney Mint struck proof sovereigns in two of them, 1887 and 1893.

The Veiled Head era of Queen Victoria, depicting the monarch in her twilight years commenced on Australia's sovereigns and half sovereigns in 1893 and continued until her death in 1901.

The Sydney Mint struck proofs only in the first year of the Veiled Head era.

The Dangar Collection sold Glendinings April 15, 1953 held two 1893 Veiled Head Proof Sovereigns (lot 229), the coins struck with a milled edge. One of the Proof Sovereigns re-appeared at Spink Auctions Australia October 1977 (lot 500) and again in November 1980 (Lot 577) and most recently in November 1989 (Lot 1321).

The Dangar Collection also held two milled edge 1893 Veiled Head Proof Half Sovereigns (lot 231). One of the 1893 Proof Half Sovereigns appeared with the proof sovereign in October 1977 (lot 500). And appeared again solo in November 1980 (Lot 673) and more recently in November 1989 (Lot 1393).

Coinworks has sold an 1893 proof pair of Sovereign and Half Sovereign (milled edge) ex Dangar, Spink Auctions 1980 and 1989. And an 1893 proof pair with the plain edge.

The Museum of Victoria plain edge proof pair formed part of the Howatt donation n 1926, acquired from the Sydney Mint on closure.   

As a summary, the Sydney Mint struck proof sovereigns and half sovereigns in 1893, the first year of the Veiled Head era (1893 - 1901). The coins were struck with a milled and plain edge. Both styles are scarce, the milled edge two. The plain edge pair just one. 

King Edward VII reigned between 1902 and 1910.

The Sydney Mint struck a Five Pounds, Two Pounds, Sovereign and Half Sovereign to a matt proof finish in 1902, each with a milled edge. The coins were struck from sand blasted dies to give the coins a matt finish. 

The 1902 four-coin Proof Set (£5, £2. sovereign and half sovereign) was offered at Glendinings in 1953 in the sale of the Henry Dangar Collection (Lot 233). It was acquired by Spink & Son Ltd London who sold it to Sydney Hagley, Adelaide collector. The set was eventually offered by Spink Auctions Australia November 1989 (Lots 1329, 1330, 1331, 1332) acquired by Barrie Winsor and sold into the Quartermaster Collection. The set is currently held by a Melbourne collector. 

The Sydney mint also produced the 1902 Proof Sovereign to a brilliant finish. Two examples were held by Henry Dangar and offered at Glendinings in 1953 as lots 234 & 235. Their whereabouts are unknown. They have never appeared at an Australian auction. 

John Sharples indicates in his studies that the existence of the 1910 Proof Sovereign has never been confirmed. 

As a summary, during the Edward VII era (1901 - 1910) proof sovereigns were struck in 1902 and 1910 only. And only one example of each is known. No proof half sovereigns were produced. Overwhelmingly rare and one of the least available sectors of the Melbourne Mint proof gold market, comprised of just two coins!

The portrait of George V appeared on Australia’s sovereigns from 1911 to 1931.

Specimen dies of the 1911 sovereign and 1911 half sovereign were preserved at Sydney until 1926. They are now thought to be at the Royal Australian Mint, Canberra. A 1911 Proof Sovereign has never been confirmed. A 1911 Proof Half Sovereign, described as a semi-matte proof was offered by Spink Auctions Australia in November 1978 (Lot 686) and is its first and last recorded sighting, the coin realising $900 against a pre-sale estimate of $750.

Two slightly different portraits were used during the George V era (1911 to 1931). The Large Head portrait between 1911 and 1928, and the Small Head portrait between 1929 and 1931.

Proof sovereigns were struck in only one year during the Large Head era, 1911. And two examples are known, both coins offered at auction in Australia, the first in November 1978 and the second in March 1985. No half sovereigns were struck. 

Examples of the 1911 Proof Sovereign are held in the Museum of Victoria, transferred on closure from the Melbourne Mint.  

Proof Sovereigns were struck in each of the three years in which the Small Head portrait of George V appeared, and two examples of each year are known held by private collectors. 

It is noted that the Museum of Victoria holds two examples of each of the Small Head years, but those coins were purchased from the Melbourne Mint, the 1929 Proof Sovereign in the year of its issue, the 1930 Proof Sovereign in 1931. And the 1931 Proof Sovereign in 1932. 

Two portraits were used during the George V era (1911 to 1931): the Large Head portrait between 1911 and 1928, and the Small Head portrait between 1929 and 1931. Extremely limited offerings, the pool of Large Head proof sovereigns is just two coins, that of the Small Head six.

Nothing compares to the allure of gold.
Particularly when it comes in the form of an Australian sovereign or half sovereign struck to PROOF quality. The coins are visually stunning, distinguished by the sharpest of detail and brilliant golden-mirror surfaces. When you look at the proofs shown above, you can only but agree. Perfection in gold.

The coins have a wonderful connection to the past.
Proof sovereigns and proof half sovereigns are the story tellers, defining an era, or a year, like no other coin. The coins can also define an occasion. And a monarch. And they tend to have a connection to a prominent person, either a dignitary, a Mint Master or an influential collector. 

The coins are genuinely rare.
Irrespective of the year in which they were struck, and the mint at which they were produced, Australia's proof sovereigns and proof half sovereigns are 'extremely rare'. We would be lucky to sight one piece at auction annually. And the reason for their incredible scarcity is that proofs were not struck every year. And of those dates that were struck as proofs, only one, perhaps two up to a maximum of three filtered their way out into the collector market.

It is estimated that there are perhaps thirty-eight Melbourne Mint proof sovereigns available to collectors, covering the complete spectrum of dates from 1872 to 1931, a span of sixty-years. The estimate on proof half sovereigns (1872 to 1915) is twenty-nine coins.

Compare their availability to our industry yardstick the 1930 Penny, where 1500 to 2000 examples are believed to exist. Or even a comparison to the Kookaburra Square Penny, struck between 1919 and 1921, where one hundred and fifty examples are believed available to collectors.

There are two other considerations that further limit their availability. As proof sovereigns and proof half sovereigns shared the same design as those coins struck for commercial usage, some of the proofs have tragically filtered their way into circulation and have been grossly mishandled, thereby marring their quality. And reducing the pool of "as struck" proof gold coins. The 1855 Sydney Mint Proof Half Sovereign, an acknowledged proof that has accidentally circulated.

The second consideration is that great coins tend to be held for the long term. The owner of "The Madrid Collection of Australian Rare Coins" held onto his proof gold coins for more than twenty years. The Spalding family for even longer. So too Tom Hadley, of Quartermaster Collection fame.

The coins have strong collector/investor appeal.
Collectors that buy in this area are all but guaranteed that the market will never be flooded with examples. So, it is a sector that offers financial stability and has been the hunting ground of investors for decades. The sector also has strength because it has widespread support amongst the Australian market. And overseas coin markets.