Jupiter daan is given on Thursday: yellow lentils (chana dal), turmeric, yellow cloth, books. 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.
Jupiter charity is turmeric, yellow cloth and sacred texts, given on Thursday to teachers, temples and schools.
An afflicted Jupiter reads as poor judgement, lost opportunities, difficulty with teachers or children, and a loss of faith in one’s own direction. Thursday observance and service to teachers are the classical answer.
Thursday. Fasting, charity and mantra japa for Jupiter all belong to that day.
The mantra, the weekday fast and the charity are safe for anyone — they address Jupiter without amplifying it. Yellow Sapphire is not: a planetary gem strengthens whatever the graha is already doing, so it needs a chart reading first.