1861: 1 Troy Ounce Platinum (semi-mfg, retail) = £ 1.60 (USD$ 7.63)
1861: 1 Troy Oz. Platinum (wholesale, wire) = £ 1.50 (USD$ 7.28)
1861: 1 Troy Oz. Platinum (mfg, stills) = £ 1.33 (USD$ 6.32-6.68)
1861: 1 Troy Oz. Platinum (mfg, stills) = 1.40 (USD$ 6.68)
1861: Retail Pt Price
Citation: The improved induction coil, Henry Minchin Noad (1861) pp.89, 91
1860- 1863: Military School expenditure, Wholesale Pt Price
Citation : Accounts and papers of the House of Commons, Vol. 35, 4/2-29/7/1864, p.134
Citation: Chemical technology; or, Chemistry in its applications to the arts ..., Vol. 1 ;Thomas Richardson1861: 1 Troy Oz. Platinum (wholesale, wire) = £ 1.50 (USD$ 7.28)
1861: 1 Troy Oz. Platinum (mfg, stills) = £ 1.33 (USD$ 6.32-6.68)
1861: 1 Troy Oz. Platinum (mfg, stills) = 1.40 (USD$ 6.68)
1861: Retail Pt Price
Citation: The improved induction coil, Henry Minchin Noad (1861) pp.89, 91
1860- 1863: Military School expenditure, Wholesale Pt Price
Citation : Accounts and papers of the House of Commons, Vol. 35, 4/2-29/7/1864, p.134
Circa 1861, Palladium presumed 'too expensive' for use in dental fillings.
Michael Faraday's famous lecture suggests the possibility of counterfeit Roubles (with cheaper Colombian ore, presumably) as a factor in the discontinuance of Platinum coinage. He also indicates the Russian coins were poorly minted and impure.
The course for Russian monetized Platinum is unknown, but otherwise an unreliable metric for the price of (im)pure Platinum ingot 1827-44.
At 639 Grains, the uncirculated 12-Rouble Coin may be assumed to contain 620 Grains Fine Pt. Conservatively estimating the Ag content of 12 circulated Silver Rouble coins shall be ~6.94 Ozt Fine Ag (at London Mint Bid, £ 1.88 - 1.95: 38 - 39 Shillings.) Faraday mistakenly calculated the Paper exchange rate (1 руб Kr. = £ 0.1488) ignoring the actual Coin premium (~+1.32%) and the correct Silver price and completely disregarding the Scrap metal value of the Platinum. Also, for this example, the value of (Silver or Platinum) Coin at Money-brokers is unknown but likely included commission.
At 30/- per Ozt (Semi-Mfg Retail), the sale value of the Platinum in a 12-Rouble Coin (.97 Pt) was not less than £ 1.94 - practically identical to the intrinsic value of 12 Silver Rouble coins in 1860/1. However, the 1862 Johnson-Matthey Bulk-Spot indicates the Platinum 12-руб Coin was only "intrinsically worth" ~£ 1.55 (31s.) In London, Silverware retailed 46% higher than its intrinsic Silver market price.
The effect of the coinage experiment on global prices was probably less significant than the global Crash of 1825, although the (attempted) Russian State valuation was quoted as a practical estimation well into the early 20th Century.
Citation: A course of six lectures on the chemical history of a candle: to which is added a Lecture on Platinum. Michael Faraday, Ed. Sir William Crookes. pp.182-4.
At auction, the 2008 price for one of the rare, surviving Platinum 6-Rouble coins was USD $74,750. The 2010 price is unknown. Lower grade 3-Rouble coins typically sold for about USD$ 4,500.
Counterfeit Sovereigns:
A counterfeit Sovereign at full-weight was probably ~4 grains Fine Au.
c. 1859: true, full-weight Sovereign's Specific Gravity = 17.575
1871 Victoria Sovereign, 8 g. (123.274 Grains = 7.988 g.)
1861 Victoria Counterfeit in Platinum , 7.92 g. (~ 122.147 Grains: plating might add ~4.5 Grains Fine Au to surface) Note the missing Die or Mint on Pt Reverse!
CNG 82, Lot: 1397. Est. $500.; SOLD 9/16/2009. USD $1,150., not incl. Buyer's Fee, ~15% or (by Weight) $664 for the Gold Sovereign and $658.50 for the Platinum Counterfeit. Where the POG was USD$ 1,016 and Pt USD$ 1,339 (and factoring +5% bullion premium), the Gold Sovereign's numismatic value would be assumed 164.42% over Retail bullion and the Platinum Coin just 100.71% over Retail likewise.
That does not appear to be the correct ratio, however. In early July 2014, Retail Ask for a highly similar Gold Sovereign (same die, condition) included a numismatic premium of 79% - 107% (w. s/h, unknown charges/taxes); on eBay the Coin sold for ~34% premium, USD$ 436. Given the large mintage of the actual Sovereign, the 2009 premium on the Gold Sovereign was not so high; more likely, it was around .
Victoria, counterfeit sovereign in platinum, 1861, young head l., rev. crowned shield of arms within wreath, very fine (St. James Auctions, Knightsbridge Coins Lot 664 Est. £250-300; SOLD 6/24/2014 for £850./ USD $1,450.) The same die crack is evident.
On eBay around 6/24/2014, the Platinum Bullion premium per Ozt was ~14%; the Coin Bullion premium was 16% - 19%/Ozt. Assuming a 20% retail charge for Coin bullion, the purely numismatic premium at auction on the 1861 Counterfeit Sovereign was an additional 253% (6/24/2014).
"Dyer examined platinum counterfeit sovereigns of four different dates, 1861, 1862, 1870 and 1872. Similar to the World Numismatic Auctions example shown across, the three 1872 counterfeits examined all had the die number 29 on the reverse. With one exception (17.44 g/cc) the relative density of the thirteen counterfeits examined varied between 19.63 to 20.36 g/cc. This is lower than the relative density of pure platinum (21.45 g/cc) but the alloy was considered to contain alloying amounts of copper. The spectrographic analysis of one coin found 3.4 percent copper. The 91.6 percent gold alloy used in sovereigns has a relative density of about 17.5 g/cc."
Assuming no other metals present, the SG Pt = 21.25, Au = 19.32, Cu = 8.8, the heaviest Specific Gravity alloy range was between 924/48/28 - 876/100/24 (92.4% - 87.6% Pt) and the lighter Specific Gravity range was between 924/19/57 - 874/73/53 (92.4% - 87.4% Pt)
It's possible that Zn or Sn was also included, although Pt must rise to 87.6% - 90.5% alloy in that case. A Platinum Counterfeit with a SG of 17.44 appears close to Hermstadt's "Artificial Gold" alloy (Pt/Cu/Zn: 832/151/17 = 17.20) with 91.7/8.7 gilding.
To achieve a closer (lower) Specific Gravity, it's not clear why counterfeiters didn't employ a higher ratio of Copper (140 parts, ~14%) and a Pt/Cu planchet heavily plated with 90/10 Au/Cu. Presumably, this was neither cost-effective or (created a different set of problems) otherwise exposed the fraud.
H. S. Shrewsbury. "Note on a counterfeit gold coin". (20-shilling piece of 1861, platinum plated with gold. Uttered at Trinidad.) Pt. Analyst, 37 (1912) p.7
20-shilling piece of 1861, platinum plated with gold: "An analysis of this metal showed it to contain 91.5% Platinum, 5% antimony and 3.4 per cent of copper." (Overman 1844: 21.22; 1865: SG 21.52; 2011: SG 21.48)
"It was found to consist of 91-5 per cent. of platinum together with some antimony and copper. It is noteworthy that gilded platinum appears to have been the metal employed on several occasions for making counterfeit sovereigns. Some of these were dated 1862 and 1863. It is to be presumed that at the time of the production of the counterfeit coins platinum was cheap enough to give the counterfeiters a fair margin of profit."
At a Specific Gravity range 20.36, the Platinum content was ~94.65%, 3% Antimony, 2.25% Copper. At SG ~19.24, Pt content was ~91.5%, 5% Antimony, 3.4%; adding (surface) Gold and diminishing the base metals might be up to 1.4% of the total weight.
Counterfeit Sovereigns:
A counterfeit Sovereign at full-weight was probably ~4 grains Fine Au.
c. 1859: true, full-weight Sovereign's Specific Gravity = 17.575
1871 Victoria Sovereign, 8 g. (123.274 Grains = 7.988 g.)
1861 Victoria Counterfeit in Platinum , 7.92 g. (~ 122.147 Grains: plating might add ~4.5 Grains Fine Au to surface) Note the missing Die or Mint on Pt Reverse!
CNG 82, Lot: 1397. Est. $500.; SOLD 9/16/2009. USD $1,150., not incl. Buyer's Fee, ~15% or (by Weight) $664 for the Gold Sovereign and $658.50 for the Platinum Counterfeit. Where the POG was USD$ 1,016 and Pt USD$ 1,339 (and factoring +5% bullion premium), the Gold Sovereign's numismatic value would be assumed 164.42% over Retail bullion and the Platinum Coin just 100.71% over Retail likewise.
That does not appear to be the correct ratio, however. In early July 2014, Retail Ask for a highly similar Gold Sovereign (same die, condition) included a numismatic premium of 79% - 107% (w. s/h, unknown charges/taxes); on eBay the Coin sold for ~34% premium, USD$ 436. Given the large mintage of the actual Sovereign, the 2009 premium on the Gold Sovereign was not so high; more likely, it was around .
Victoria, counterfeit sovereign in platinum, 1861, young head l., rev. crowned shield of arms within wreath, very fine (St. James Auctions, Knightsbridge Coins Lot 664 Est. £250-300; SOLD 6/24/2014 for £850./ USD $1,450.) The same die crack is evident.
On eBay around 6/24/2014, the Platinum Bullion premium per Ozt was ~14%; the Coin Bullion premium was 16% - 19%/Ozt. Assuming a 20% retail charge for Coin bullion, the purely numismatic premium at auction on the 1861 Counterfeit Sovereign was an additional 253% (6/24/2014).
"Dyer examined platinum counterfeit sovereigns of four different dates, 1861, 1862, 1870 and 1872. Similar to the World Numismatic Auctions example shown across, the three 1872 counterfeits examined all had the die number 29 on the reverse. With one exception (17.44 g/cc) the relative density of the thirteen counterfeits examined varied between 19.63 to 20.36 g/cc. This is lower than the relative density of pure platinum (21.45 g/cc) but the alloy was considered to contain alloying amounts of copper. The spectrographic analysis of one coin found 3.4 percent copper. The 91.6 percent gold alloy used in sovereigns has a relative density of about 17.5 g/cc."
Assuming no other metals present, the SG Pt = 21.25, Au = 19.32, Cu = 8.8, the heaviest Specific Gravity alloy range was between 924/48/28 - 876/100/24 (92.4% - 87.6% Pt) and the lighter Specific Gravity range was between 924/19/57 - 874/73/53 (92.4% - 87.4% Pt)
It's possible that Zn or Sn was also included, although Pt must rise to 87.6% - 90.5% alloy in that case. A Platinum Counterfeit with a SG of 17.44 appears close to Hermstadt's "Artificial Gold" alloy (Pt/Cu/Zn: 832/151/17 = 17.20) with 91.7/8.7 gilding.
To achieve a closer (lower) Specific Gravity, it's not clear why counterfeiters didn't employ a higher ratio of Copper (140 parts, ~14%) and a Pt/Cu planchet heavily plated with 90/10 Au/Cu. Presumably, this was neither cost-effective or (created a different set of problems) otherwise exposed the fraud.
H. S. Shrewsbury. "Note on a counterfeit gold coin". (20-shilling piece of 1861, platinum plated with gold. Uttered at Trinidad.) Pt. Analyst, 37 (1912) p.7
20-shilling piece of 1861, platinum plated with gold: "An analysis of this metal showed it to contain 91.5% Platinum, 5% antimony and 3.4 per cent of copper." (Overman 1844: 21.22; 1865: SG 21.52; 2011: SG 21.48)
"It was found to consist of 91-5 per cent. of platinum together with some antimony and copper. It is noteworthy that gilded platinum appears to have been the metal employed on several occasions for making counterfeit sovereigns. Some of these were dated 1862 and 1863. It is to be presumed that at the time of the production of the counterfeit coins platinum was cheap enough to give the counterfeiters a fair margin of profit."
At a Specific Gravity range 20.36, the Platinum content was ~94.65%, 3% Antimony, 2.25% Copper. At SG ~19.24, Pt content was ~91.5%, 5% Antimony, 3.4%; adding (surface) Gold and diminishing the base metals might be up to 1.4% of the total weight.
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