Some people put various interpretations, to differentiate between natural stones, artificial and synthetic. This definition often varies with the individual.
Made Man - In general, the term is used for stones that are made in the laboratory or factory. These include stones through the use of modern equipment for its growth. It should be remembered, too, there is a cheaper process and the process is at a high cost. Some stones are made in the laboratory and chemical features in common with the original, such as ruby (Al2O3) and there are stones made of natural stones to imitate nature, such as YAG (yttrium Aluminum Garnet).
Artificial (immitation) - This term is used for stones that are made to mimic a natural material. Glass is often used to imitate natural gemstones. However, some natural stones are also used to imitate other precious stones are usually more valuable. For example, spinel is used to imitate ruby. So, there is an opinion saying the term is not necessarily used for artificial gems. Typically, an artificial 100% may not necessarily mimic the physical and chemical properties of a gemstone is natural. For example Peridot forsterite is made by man but are colored as so they can look like tanzanite on the market.
Synthetics - The term used for synthetic gemstone made the same chemical properties with natural gemstones such as ruby, sapphire (Al2O3) and emerald (Be3Al2 (SiO3) 6), making his name as a synthetic ruby, synthetic sapphire or synthetic emeralds.Note: In the modern market, we never hear the dealers who sell synthetic stones used the term "synthetic" rather they use the term "artificial" or another term. Thus, the term "artificial" is used as an example artificial rubies or emeralds made. One feature (which may not be preferred by some experts) on the synthetic rock is chemical and optical properties of synthetic rock is very similar to the original. Depending on the synthetic rocks made, some synthetic rocks indicate the nature, structure and characteristics match the original rocks that made it difficult to distinguish. There are some cases, synthetic rocks are indistinguishable from the original.