The lucky gemstone for Sagittarius individuals is Yellow Sapphire. When Jupiter is unfavorable, they wear Yellow Sapphire weighing 3 to 4 carats on the index finger on Thursday after chanting the mantra 'Om Hram Hreem Hroum Sah Brihaspataye Namah' 19,000 times. In Western culture, they also consider Neelam, Doodhiya, and Sulemani gemstones auspicious for Sagittarius.