Little Gem Girl Mexican Fire Opal Dragons Breath Pendant 18 Inch Necklace Silver Victorian Heart Charm Setting Mexican Fire Opal Dragon's Breath glass cabachon - Colors shift from lightening strikes of blues to scarlet red depending on how the light hits it The flashes of color from within the stone are known as the "breath" from which the name is derived. Mexican Opals were first used in jewelry in the early 1900s to simulate fire/jelly opals. Highly collectible and rare  this lovely stone is a certain conversation piece and will become a cherished favorite. Glass cabochon is 18mm or approximately .79 inches in diameter. Victorian style silver heart setting holds the Mexican Fire Opal and comes on an 18 inch link chain Comes with an organza bag - ready for gift giving! Handcrafted in the USA by Little Gem Girl - a small handmade business!