বুধ daan is given on বুধবার: মূংগ দাল, হরা বস্ত্র, পুস্তকেং, কলম ঔর লেখন সামগ্রী. Charity addresses a graha without amplifying it, which is why it is prescribed where a gemstone is withheld.
Daan is charity aimed at a specific graha, given on its day and matched to its significations. Classically it is the remedy that works when a gemstone would be dangerous — it addresses the planet without amplifying it, which is why it is prescribed for Rahu and Saturn where stones are withheld.
Mercury charity is books, stationery and green moong, given on Wednesday to students, schools and libraries.
A weak Mercury shows as scattered thinking, careless speech, difficulty finishing what was started, and nervous restlessness. Wednesday practice and service to students are the classical response.
বুধবার. Fasting, charity and mantra japa for বুধ all belong to that day.
The mantra, the weekday fast and the charity are safe for anyone — they address বুধ without amplifying it. পন্না is not: a planetary gem strengthens whatever the graha is already doing, so it needs a chart reading first.