Emeralds are typically found with natural internal fissures which are known as “gardens”. Long ago it was discovered that the simple application of oils would greatly reduce the visibility of these inclusions, thereby noticeably enhancing the emerald is appearance. This practice has become traditional and is accepted throughout the precious gem trade. Emeralds are also known to be not quite as durable as diamond, ruby and sapphire. This fact combined with the common practice of oiling requires the owner to take a little extra care of their wonderful green gems.It is also common to oil emeralds to enhance their appearance, usually done as a post-lapidary process in the country of origin. This is acceptable in the gem industry as long as no coloring agents are used.Ruby Heating Treatment:
Natural rubies are also treated to enhance its color, clarity and transparency. Most popular treatment is heat treatment. Natural rubies are costlier than treated rubies. There are some other treatments such as glass filling and led filling. Glass filling enhances clarity of rubies and led filling enhances both clarity and color. However, led filling is injurious to health.Sapphire Heating Treatment:
Yes, a natural sapphire is a sapphire crystal that has been created in the ground - but the color and clarity (what you are paying for in a sapphire) is created from a heating process that would have never occurred naturally in the stone that is being shown. The truth is that almost everything you will see in sapphires anywhere is treated, and treating is not a simple process. It is a sophisticated procedure that has taken decades to perfect by experienced enhancement specialists. The stones are not just thrown in an oven and baked like cookies.
Treating and heating a stone is a very involved process that significantly changes the original appearance (and value) of the rough crystal that came out of the ground. Ultra-high temperature gas furnaces heat these stones for a period of 3-10 days, at or above the melting point of the crystal (1800°C). Additives such as glass and coloring agents can be include_onced in the heating process in order to fill in natural cavities and cracks in the sapphires. Coloring agents are then diffused into the heating process in many cases, where the coloring of the sapphire is completely and radically altered. Trying to determine what you are buying is now a scientific research project in most cases.