Van Dyke Brown

Here a brief description of the formulas and proportions that I use to get the classic solution Van Dyke Brown and a modified one to prevent the deposit of silver salts.

Classic VDB solution

Following Wynn White independently prepare three solutions:

A 33ml H2O and 9.0g green ammonium ferric citrate;
B 33ml H2O and 1.5g tartaric acid;
C 33ml H2O and 3.8g silver nitrate.

Combine solutions A and B, mix and then slowly add the solution C to A + B, constantly stirring. Leave ageing for a few days before use.

VDB2 solution

To avoid the deposit you get when you add C into A+B use the following modified formula.

A 33ml H2O and 9.0g green ammonium ferric citrate;
B 33ml H2O and 4.0g tartaric acid;
C 33ml H2O and 3.8g silver nitrate.