Anandakanda 2.1.163

2.1.163

tacchuṣkaṃ sampuṭe dhāmyaṃ khadirāṅgārakairdṛḍham /
ūrdhvapātre nivāryātha siñcedamlena kena tam //

When dried, it should be blown firmly in a sealed vessel with khadira charcoal. / Then, checking it in the upper vessel, one should sprinkle it with a certain sour liquid.