Lapis lazuli is a bright blue gemstone with golden inclusions. These inclusions are pyrite, and actually make the stone more valuable rather than less. Historically it has not only been worn as a valuable gemstone, but the Renaissance painters ground it up to make a deep, sparkling blue paint for their creative works. Whether you are buying an uncut lapis lazuli as an art object or considering investing in a piece of jewelry, make sure to consider the unique aspects of this stone before buying.

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Look for sparkle. The value of a lapis lazuli is largely determined by how many pyrite inclusions it has. However, these inclusions should be visible when the gem is set, so make sure to factor in the location of these inclusions when you are considering buying a gem. You will want at least one side to look almost like a starry sky.

Examine the surface for scratches. Lapis lazuli is a soft gemstone and is easily damaged in transit. Examine the surface of the stone for nicks and scratches. These can be polished away, but if you are buying a flawed stone then you can definitely negotiate based on surface problems.

Ask about protective coatings. Lapis lazuli is often coated with a clear resin to protect the stone. Ask about the type of coating to make sure that it is not colored or tinted in any way. The coating may wear off over time and have to be reapplied, but the stone beneath will remain sound.

Evaluate the color. The most valuable color of lapis lazuli is a deep, royal blue. However, it comes in shades from light blue to a dark, almost navy blue. You should base your final decision on whatever color makes you happiest and looks best on you if you want the stone for jewelry.

Find out how the stone has been displayed. Lapis lazuli should not be exposed to sunlight for extended periods of time. Many jewelers try to incorporate some natural light into their showrooms both because it makes certain gems look more appealing and because many buyers do not trust showroom lighting and want to view the gems in a different setting. However, if your lapis lazuli has been sitting in the sun, it may not be as brilliant as it once was.