UK, 1882 : Platino-iridium wire

1882: 1 Troy Ounce platina (UK: bulk, .999) ~ £ 1.46 (USD$ 7.09)

1882: 1 Troy Oz. Platinum (Sheet, Retail) = £ 2.00 (USD$ 9.78)

Citation: Crystal palace. International electric exhibition, 1881-82. Official Guide


The base-price for all components of a No.2 Sized Battery (Bunsen's) was £ 0.3750

Assuming the base-price for the Grove No.1 Sized Battery without Platinum was £ 0.1518
(~3s. 0.5d) 12.375 in² = 79.839 cm² Platinum Foil cost £ 0.2982 : 71.56 Grains or 0.149 Ozt

Assuming the base-price for the Grove No.2 Sized Battery without Platinum was £ 0.1518
(~3s. 0.5d) 22.75in² = 146.77cm² Platinum Foil cost £ 0.5482 : 131.57 Grains or 0.274 Ozt

At this rate, 144in² = 929.03cm² = £ 3.47 (~£3 9s. 5d.) also consistent with "1d. per Grain":

1882: 1 Troy Oz. Platinum (Sheet, Retail) = £ 2.00


 

Citation: How to work with the spectroscope.  John Browning (1882)


1882/3: 1 Troy Ounce Platino-iridium (refined, retail) = £ 2.50 (USD$ 17.40) 
1882: 1 Troy Ounce Platinum (refined, retail) = £ 2.00 (USD$ 9.78)

1883/4: 1 Troy Ounce Platinum (refined, retail) = £ 1.80 (USD$ 8.73)


Citation: The Electrician and electrical engineer, Vol. 4 (1885) p.61


Uncertain, c.1882/3:


 

Dental Platinum, Retail Cost