UK, 19th C.: Spatulas, by Weight (Griffin's Catalogue)

1866:
Griffin's 1866 Catalogue suggests a 5s. per Ozt charge on the manufacture of simple Platinumware.

1866: 1 Troy Oz. Platinum (Unmfg, Retail) = £ 1.65 (USD$ 11.31)
1866: 1 Ozt. Platinum (Spatula, Retail) = £ 1.90 (USD$ 13.01)


Citation: Chemical Handicraft: A Classified and Descriptive Catalogue of Chemical ... (1866) John Joseph Griffin, p.438

1877:
Griffin's 1877 Catalogue shows an older, erroneous Platinum Price. Assuming the same 5s. per Ozt charge on manufacture of simple Platinumware, the correct Platinum Price may be ascertained.

1877: 1 Ozt. Platinum (Semi-Mfg) = £ 1.65 (USD$ 8.51)
1877: 1 Ozt. Platinum (Semi-Mfg) = £ 2.35 (USD$ 12.12)
1877: 1 Ozt. Platinum (Mfg: Spatula) = £ 2.60 (USD$ 13.41)

Citation: Chemical handicraft: A classified and descriptive catalogue of chemical ... John Joseph Griffin (1877), p.460

1877: Estimated

1.0 in. Length = 55 grains 

1.5 in. Length = 65 grains

2 in. Length = 70 grains

2.5 in. Length = 80 grains

3 in. Length = 100 grains

3.5 in. Length = 130 grains

4 in. Length = 170 grains

4.5 in. Length = 200 grains

6 in. Length = 300 grains