For each lagna there are adverse gemstones as given below.
Mesha - Emerald, Diamond
Rishabha - Pearl, Coral, Yellow Sapphire
Mithuna - Ruby, Pearl, Coral, Yellow sapphire
Kataka - Emerald, Diamond, Blue Sapphire
Simha - Diamond, Blue Sapphire
Kanya - Ruby, Coral, Yellow Sapphire
Tula - Ruby, Emerald, Yellow Sapphire
Vrischika - Diamond, Emerald
Dhanus - Diamond, Pearl, Blue Sapphire
Makara - Pearl, Ruby, Yellow Sapphire
Kumbha - Ruby, Coral, Pearl
Meena - Emerald, Diamond, Blue Sapphire.