UK, 1840

1839: 1 Troy Oz. Platinum (unrefined bulk ingot; Paris) ~ (USD$ 3. - 3.20)

1840: 1 Troy Ounce Platinum (Semi-Mfg, Ret.) = £ 1.50 
1841: 1 Troy Ounce Platinum (Semi-Mfg, Ret.) = £ 1.50 (USD$ 7.50)
1842: 1 Troy Ounce Platinum (Semi-Mfg, Ret.) = £ 1.50 (USD$ 7.00)

At the end of Alfred Smee's Elements of electro-metallurgy (1840) 

Citation:  Palmer's New Catalogue, with 300 Engravings of Apparatus, illustrative of Chemistry, Pneumatics, Electricity, Optics, etc., with prices ; (1840) p. p. 20










c.1839/40: Platinized Silver


Citation: Elements of electro-metallurgy, Alfred Smee (1840) pp.

c.1840:  Silver was estimated at 1/5th the Price of Platinum






In Advertisements: Watkins and Hill's voltaic or galvanic instruments (1840) "ten pair" would be £ 8.40 (1 Element = £ 0.84), highest catalogue retail for the 0.5 x 4.0 Foil Element.
Smaller Element presumably 0.5 x 2.0 Foi.

SET OF TEN PAIRS OF GROVE'S FLAT PLATINUM AND ZINC P. cells in an ordinary sized Wollaston's porcelain trough, to liberate twenty- ...[six? cubic inches] of the mixed gases per minute, 8£ . 8s.

SET OF FIVE PAIR OF GROVE'S FLAT PLATINUM AND ZINC... liberate thirteen cubic inches of the mixed gases per minute, 4£ . 4s.

SINGLE PAIR OF GROVE'S FLAT PLATINUM AND ZINC PLATES...in Porcelain trough, 13s.

PAIR OF SQUARE PLATINUM DISCS OR PLATES, on Glass Column: decomposition of the alkalies by the influence of voltaic agency, 1£ . 10s. to 3£ . 3s.

In a comprehensive evaluation of various battery types, William Sturgeon grappled with the question of cost.  His 10-Cell Grove's Battery is estimated at £ 7. (1 Element = £ 0.70)

Citation: The annals of electricity magnetism and chemistry and guardian of ..., Vol. 5 (1840)





April 13, 1840: 'Quantity' Battery and 'Intensity' Battery

Quantity' Battery: 320 Sq. In. of Platinum Plate ; 640 Sq. In. surface area, so 1 Element was 8 Sq. In. ("about four square feet" is only 576 Sq. In. ; more accurate is "about four and a half square feet" = 648 Sq. In.) 

'Intensity' Battery: 600 Sq. In. of Platinum Plate ; 1200 Sq. In. surface area, so 1 Element was 12 Sq. In. 
 
The Annals of Electricity, Magnetism, and Chemistry; and Guardian ..., Vol. 4

 











April, 1840:

To calculate the amount of Platinum in a Watkin's Grove's Cell, compare the rate at which water is decomposed into Hydrogen and Oxygen.  The larger Battery demonstrated by Grove (with 40 Platinum-Zinc Cells in 5 Plates total: 48 square inches Platinum in total, 24 inches of double sided-sided Platinum: 4.8 sq. in. of Platinum Sheet per Plate) produced 110 cubic inches of gases per minute, or 2.75 cu. in. gases per Cell.

For Watkin's & Hill's smaller battery of just 5 Grove Platinum-Zinc Cells advertising 13 cubic inches of gases per minute, each Cell produced 2.60 cu. in. gases per Cell, so each Watkin's & Hill's Cell would have ~4.54 sq. in. of Platinum Sheet per Plate.

Watkin's &Hill's Cell for this battery (with ~4.54 sq. in. of Platinum Sheet) cost £ 0.84; the cheaper "Single Pair" £ 0.65 was certainly smaller w/ less Platinum.
Palmer's Catalogue of 1841 offered the 'larger cell'  Grove Platinum-Zinc 6-Cell Battery at £ 0.4167 ; the 'smaller cell' was just £ 0.2917 per Cell.

The cost of batteries (and probably Platinum) was falling dramatically.

Citation: The Metropolitan Magazine, Vol. 27, No. 58


Smee notes that in 1840 the assayer's charge for pure refining Silver was  £ 0.05 over the Market-Price, an 18.4% increase for the Producer's Price. 

Commercial Silver Nitrate (unknown purity) was ~30.6% over the Market-Price for Silver.

In period wholesale/retail catalogues selling 'pure Silver foil' for £ 0.425, platinised Silver foil sold for £ 0.475 or about 12% over the Market-Price for Fine Silver. 

 


Talbot's engine, with Grove's Battery: 4 Large Elements (198 Sq. In. Platinum Plate) where
1 Element had 49.5 Sq. In. Platinum Plate (99 Sq. In. surface)
 



April 1840: Where 3 Sovereigns = 0.77 Ozt; 23.964 g., presumed 9-carat

1839/40: 1 Ozt. Gold (Mint) = £ 4.241
1839/40: 1 Ozt. Gold 9-Carat Chain = £ 5.14

1839/40: 1 Ozt. Gold (9-Carat Chain, @.999) = £  13.70 
1839/40: 1 Ozt. Gold .999 (9-Carat Chain, 2.67 Ozt) = £  11.95