CR rubies are rubies that have the same natural contents and composition as rubies that are mined, but CR rubies are created in a lab. The "CR" stands for "created." CR rubies are quite hard to distinguish from real rubies, but they cost substantially less to create, refine and set in jewelry. If you are considering buying a CR ruby or a natural ruby, you should understand exactly what the differences are in order to make the best decision possible for you. However, remember that a CR ruby is in fact a ruby; it was created in a lab under high heat rather than under the earth.
CR rubies are created in laboratories. They are intended to make an extremely expensive gemstone more accessible and available to everyone. Rubies are quite rare and can be extraordinarily pricey, while CR rubies are much more practical and nearly impossible to distinguish from natural rubies. CR rubies are great for central stones in ring settings because you can get a large, nearly perfect stone for a fraction of the cost of a mined one.
CR rubies are nearly identical to natural rubies in every way. They have the same chemical composition and qualities as natural stones. You may actually be able to identify a CR ruby because it is too perfect. If your stone has no flaws and is the perfect, bright shade of red but does not cost an arm and a leg, this is a good indication you are looking at a CR ruby.
Chrome gives natural and CR rubies their red color. If it were not for chrome, rubies would be colorless pieces of the mineral corundum. Iron is used in CR rubies to make the colors brighter. Because they are "baked" in a lab at extremely high temperatures to create a red stone from the basic materials of chrome, iron and corundum, CR rubies tend to be flawless. Natural rubies are not protected in a pristine environment from the elements while they are created, so they usually have flaws. CR rubies also are easier to cut than natural rubies, even though their chemical compositions are identical. This is largely due to their consistent texture that is a result of the artificial creation. As a result, CR rubies are often cut to have extremely bright facets.
If you are considering a CR ruby purchase, you need to factor in the reason for the investment. If you are buying jewelry as an investment, then you should remember that you will probably have a hard time reselling a CR ruby piece unless it is a unique, custom design. Also, if you are buying the ruby as a gift, consider whether the recipient would mind if they found out their stone was a CR ruby. Most people do not care, but in some cases a person might prefer to have a smaller or different natural stone rather than a CR ruby.
Whenever you are considering a major jewelry purchase, you should have the stones, settings and certifications examined by a trusted jeweler. Once you have purchased an item, you have nearly no recourse should that item turn out to be something other than what you believed when you bought it. Make sure you know what you are buying before you make the investment.