This is 100g of Potassium Ferricyanide from Photographers' Formulary. It is mainly used in bleach baths, such as a bleach prior to sulfide toning, as well as a component in iron printing processes and dye-toning formulas.
Photographers' Formulary 10-1010 100G Specs
| Synonyms | Ferricyanide Ferricyanide of potash Red praised of potash  | 
| Appearance | Bright red, crystalline powder Odorless  | 
| Uses | Principal use is in conjunction with hypo, forming Farmer's Reducer Used in iron printing processes As a bleach before sulfide toning, and dye toning formulas  | 
| Chemical Formula | K3Fe(CN)6 | 
| Notes | Keep protected from light | 
| Weight | 3.5 oz / 100 g | 
| Package Weight | 0.25 lb | 
| Box Dimensions (LxWxH) | 3.5 x 2.3 x 2.2" | 
UPC: 675152100030