UK, 1806: Retail Platina

Dr. Wollaston's commercial production coincided with and probably supported a very stable period in platina prices.  John Johnson's platina sale to Wollaston started in December 1806, with large lot sales (1,000 - 1,750 ozt) in 1808.

Of 7,015 Ozt platina processed 1800-1806, Wollaston produced 5,350 Ozt Platinum: the ore was ~76.27% Pt.

Wollaston assumed Johnson purchased 1 Libra for S$ 6. silver; at 1806 forex on New Dollars:

1806: 1 Troy Ounce platina (Importer's Cost, 76.3% ore)  = £ 0.0975 - 0.1063
1806: 1 Troy Oz Pt (Importer's Cost, .999)  = £ 0.1278 - 0.1394
1806: 1 Troy Oz Pt (Wollaston's Labor, Per Ozt)  = £ 0.10
1806: 1 Troy Oz Platinum (Wollaston's Cost Basis, .999)  = £ 0.2278 - 0.2394
 
At English Retail, 1 Libra cost ~£ 4. (S$ 17.59 - 17.85)

1806: 1 Troy Ounce platina (76.3% ore, retail)  = £ 0.2743 (USD$ 1.22)
1806: 1 Troy Oz .999 Pt (Ore at Purity)  = £ 0.3596 (USD$ 1.60)
1806: 1 Troy Oz Pt (Labor Cost, Sheet)  = £ 0.0875 (USD$ 0.39)
1806: 1 Troy Oz Platinum (Producer Cost, Sheet)  = £ 0.4471 (USD$ 1.99)

1806: 1 Troy Oz Silver (Fine Ag, retail)  = £ 0.3161 (USD$ 1.406)

1805: 1 Troy Ounce platina (Wollaston: ore, bulk)  = £ 0.23 (USD$ 0.98)

Where 2.28 Ozt cost £ 0.625:

1806:

Citation: The Technical repository, Edit.Thomas Gill (patent-agent) p.124