Gobhilagrihyasutra 3.8.6

3.8.6

brāhmaṇān bhojayitvā, svayaṃ bhuktvā jātuṣān maṇīn sarvauṣadhimiśrān ābadhnīran svastyayanārtham.

After he has entertained the Brâhmanas with food and has eaten himself, (the sacrificer and his family) should tie (to their arms, necks, &c.) amulets made of lac together with all sorts of herbs, for the sake of prosperity.