In Sri Lankan ancestral astrology, dark blue sapphire considers removing the evil influence of the planet Saturn. They use very dark blue gemstones which have the same color as a crow to make silver rings as an astrological remedy. Actually from history, Sri Lanka is a land of blue stones.
Gem and crystals such as chrysoberyl and moonstones use for many centuries for healing, taking prosperity, and protection cause of their Mystical Energies.
Sapphires and rubies are fancy color stones that people use for jewelry and in Vedic Astrology, they are commonly used as remedies for planetary malfunctions. Sri Lanka is a country of gemstones called the Land of Blue Sapphires.