The differences between synthetic and simulated can be the most confusing, although the term cultured can throw people off as well. What do they mean?

Synthetic:

A synthetic stone is made in a laboratory to be as close as possible to the natural stone. These look like exceptionally clean, exceptionally colored (in the case of colored gemstones) stones that are priced well below what you would expect to pay for a natural stone of such color and clarity.

Some synthetic stones are so hard to tell from the highest quality natural gemstones that it takes a professional with a microscope to do it. A few even have special chemical markers added just so that they can be told from natural stones.

However the difference will be pretty obvious in some stores when you look at precious gemstones such as rubies and emeralds. The best of these are very hard to come by, and the synthetics shine out.

Synthetic gemstones may also be called lab created, lab grown or be under a brand name. A reputable jeweler will tell you up front whether a stone you are looking at is synthetic.

Simulated:

A simulated gemstone has the color of the stone it is imitating and little else. They are even cheaper than synthetic stones, and may even be nothing more than colored glass or plastic.

They may be nice as gifts for children, but few others will really appreciate a simulated gemstone.

Cultured:

This term is most often associated with pearls, but some synthetic gemstones are also created in a process called culturing. A bit of material is used for the gemstone or pearl to form around.

With pearls, this is done in the oyster with an irritant. Most pearls you buy these days are cultured. As they are formed in the oyster just as a natural pearl is, the one question is how long they were allowed to grow in the oyster. This is not information jewelers will typically have, but if a cultured pearl has poor luster it probably was not in the oyster long enough and will wear down quickly.

With gemstones, a bit of the natural stone is placed in with dissolved material to form stones such as sapphires, rubies and emeralds. The synthetic crystal grows around the natural stone, just as the pearl grows around the irritant, which is why they are called cultured.