Presumably at the same rate, 1 Inch = $0.6059 or 14.87 Inches per Ozt.
A major vendor of Platinum, S.S. White Co. announced a (specie) price reduction in 1875, then another to currency rates (Greenbacks) in 1876.
The wholesale premium for pure Silver was >75% ; for pure Gold (@ $1.20 per pennyweight) the wholesale premium was
1877: 1 Troy Oz. Platinum (Semi-Mfg, sheet, Retail) = USD$ 11.88
Citation: Samuel S. White Catalogue of Dental Instruments and Equipment ; Samuel Stockton White, Audrey B. Davis (1876) p. 269
1877/8: an imported French Gramme weight set cost $ 9.51
1876: 1 Troy Oz. Platinum (Mfg, Ret.) = USD$ 46.66 ($ 41.85)
1877/8: a Gramme weight set @ Fr. 5.14375 cost $ 3.89
1856: a Gramme weight set @ Fr. 5.40 cost USD$ 4.63
Poorly understood valuation crisis in Russian Platinum coin, by Senator John P. Jones (R-NV, and owner of the Crown Point Mine)