Ratna and graha correspondence
Ruby for Surya, pearl for Chandra, coral for Mangal, emerald for Budh, yellow sapphire for Guru, diamond for Shukra, blue sapphire for Shani, hessonite for Rahu and cat's eye for Ketu — classical texts link each ratna to a planet's shakti.
Wearing a stone for a planet that rules difficult houses in your chart can amplify struggle rather than ease it. This is why blanket "wear a neelam for Shani" advice fails.
Trial and authenticity
Reputable Jyotishis suggest trial periods — keeping the ratna under the pillow or in the pocket before setting in ring or pendant. Heat, dreams and subtle shifts are observed.
Untreated, properly weighed stones in suitable metal matter. A cracked or synthetic gem carries no upaya shakti.
Alternatives to ratna
Mantra japa, daan on the graha's day, fasting and yantra worship often suffice. Ratna is not mandatory for every affliction — nor is it a shortcut around karma.
Upaya without shraddha is ornament. Combine gemstone where indicated with disciplined practice and ethical action.