Ruby is one of the traditional cardinal gems, together with amethyst, sapphire, emerald, and diamond. Jewels are ranked in the order of amethyst, ruby, emerald, and diamond. These beaches have water that varies in color from emerald green to turquoise blue. Notable gemstones which contain beryllium include beryl (aquamarine, emerald) and chrysoberyl. Other cyclosilicates include beryl, AlBeSiO, whose varieties include the gemstones emerald (green) and aquamarine (bluish). There are four cups available (Ruby, Sapphire, Emerald, and Diamond) with five tracks in each. Women could not use ornaments made from gold, jade, pearl or emerald. Shadow repels it, allowing Knuckles to deactivate the Chaos Emeralds with the Master Emerald. The name derives from the typical appearance of the emerald gemstone. Muzo refers to a warm, grassy-green emerald, with hints of yellow. There are four tiers where three elite tiers are Gold, Emerald, and Paragon. Green is a symbol of Ireland, which is often referred to as the "Emerald Isle". The same is true for the beryllium compounds beryl and emerald. These included the Goodenough, Toughnut, Contention, Grand Central, Lucky Cuss, Emerald, and Silver Thread. Knuckles is the guardian of the Master Emerald, which grants the island its levitation powers.