JULY BIRTHSTONE The ruby is the king of precious gems. Ruby, the king of precious gems, is the birthstone for fortunate folks born in July. Whether you're showing your love for someone born in July, or celebrating a 15th or 40th wedding anniversary, there's no better gift than ruby gemstone jewelry. Ruby Ruby is the red variety of the mineral corundum, colored by the element chromium. All other colors of gem-quality corundum are called sapphire, which means color is key for this royal stone. Accordingly, the name "ruby" comes from rubeus, MORE OVERVIEW HISTORY HOW TO BUY Find a Jeweler Search for an American Gem Society member jewelry store. Search