UK, 1874/84: Metal Prices

Citing a German source and not adjusting for unknown forex, the following tables may suggest a decline in US PGM prices in this period.

1874: 1 Troy Ounce Osmium (whols.) = £ 4.90 (USD$ 26.58)

1874: 1 Troy Ounce Iridium (whols.) = £ 4.80 (USD$ 26.)

1874: 1 Troy Ounce Platinum (whols.) = £ 1.74 (USD$ 9.73)

1874: 1 Troy Ounce Platinum (mfg., retail) ~ £ 2. (USD$ 10.84)

1874: 1 Troy Ounce Gold (whols.) = £ 4.30 (USD$ 23.33)

1884: 1 Troy Ounce Osmium (whols.) = £ 4.25 (USD$ 20.62)

1884: 1 Troy Ounce Iridium (whols.) = £ 3.09 (USD$ 14.87)

1884: 1 Troy Ounce Platinum (whols. = £ 1.47 (USD$ 7.11)

1874: Platinum crucibles were about "half the price of pure Gold":

c.1874/5 Horne Catalogue: