gold ink

Ingredients

eggshell, quicksilver, tar, wax

Preparation Steps

Original Recipe Text

[To make] gold ink: A wisdom [of] how to write in gold. Pierce an egg and remove everything from its inside. After that, fill it with quicksilver and seal it very thorough[ly] with tar or wax and place under a hen with the rest of the eggs that are about to hatch, until they hatch. Then [when it happens], take what is inside the [egg] and write with it. It will be truly like gold. Tested. (p. 294)

Evidence

"To produce ink of a golden hue, one curious recipe recommends emptying an eggshell through a small puncture and filling it with mercury. After the shell was sealed with wax or tar, it was to be placed beneath a hen among her eggs which were waiting to hatch. In this case, the mercury-egg at the time of hatching would contain an ink that has all the appearances of gold."

Remarks

The recipe relies on the 'natural calefaction by the body of an animal' to induce elemental transformation of mercury into a gold-like writing fluid (p. 295). This specific recipe is noted as being transcultural, appearing in various configurations across European craft books and Jewish compilations (p. 294, 298). The compiler, Elhanan, explicitly marks this recipe as 'Tested' (p. 294).