Refers to how transparent a gemstone is and how many inclusions are seen. A lab created ruby typically has perfect clarity – meaning there are no lines, cracks, or imperfections and you can see through the stone. Clarity is a large factor in the value of most gemstones, particularly those labeled precious. Diamonds are rated on the diamond clarity scale, ranging from flawless to I3 (many highly visible inclusions). Other gemstones are typically graded on a simpler scale.