Buying a White Sapphire

• Color: Overall, a priority.  For white sapphire, any noticeable under tone should be negligible (less color the better). Place the stone on a piece of white paper and see if you notice any yellow, blue, green or brown, remember in the case of white sapphire less color is the key.

• Cut: Especially important in white sapphire. Many times a good cut on a white (colorless) sapphire can bring out the brilliance in the stone to its maximum potential. For example a plain emerald cut white sapphire will appear dull compared to a radiant emerald cut white sapphire even if they were cut from the same piece of "rough" sapphire crystal.

• Enhancements:  Today, the vast majority of white sapphires are heat-treated to improve their appearance. Sometimes it's used to burn out any trace of color to give a purer appearance. The resulting stones are completely stable, as a matter of fact heat treatment of gemstones is a science dating back to the Roman times. In lower qualities, heat treated stones sell for roughly the same as untreated stones of the same quality. However, for finer qualities, untreated stones fetch a premium that is sometimes 50% or more when compared with treated stones of similar quality. As with all precious stones, it is a good practice to have any major purchases tested by a reputable gem lab, such as the GIA or AGTA, to determine if a gem is enhanced.

Common Terms used to describe clarity

• Opaque, meaning the stone will not transmit light through it.
  

•  Translucent, or cloudy, meaning that the stone transmits light, but you cannot see clearly through it.
  

•  Heavily Included, meaning that the stone is transparent, but the stone is littered with inclusions, which are very visible without magnification.
  

•  Moderately Included, meaning that the stone is transparent, but there are several inclusions, which are visible without magnification.
  

•  Slightly Included, meaning that the stone has some very minor inclusions which may be visible without magnification.
  

• •Very Slightly Included, or eye-clean, meaning that the stone has some very minor inclusions that are not readily visible without magnification. Some inclusions may be visible without magnification once you see them under magnification and know exactly where to look.
  

• Very Very Slightly Included, or loupe clean, meaning that the stone has some very very minor inclusions which are difficult to see under magnification. 
  
  Common Inclusions in White Sapphire?

• Fractures & Cracks - These are not uncommon. Depending on the type, they can also be referred to as cleavages or feathers. Small cracks are generally not a problem unless their location significantly mars the look of the gem, but deep, long fractures, especially if they break the surface, can case the gem to break under the right conditions (and usually doesn't look all that great), but that's not to say a well cut diamond, for instance, of very good color with these type of larger or surface breaking cracks, might not be durable, set nicely into jewelry and still dance with sparkle and look nice. It's that "eye of the beholder" thing, (and paying a fair price for it).
  
• Crystals - These appear in many gems and can be so tiny that a microscope has trouble seeing them, up to large and interesting or ugly. They are solid minerals of different sizes and shapes as inclusions in the gem when they were formed in the earth. Generally larger ones affect clarity and lower value, but sometimes if interesting and well placed, can be attractive or a collectors "thing".
  
• Voids - These too are called Crystals, but are actually hollow in the shape of a crystal and the same clarity criteria apply.
  
• Halos - These are cracks or fractures that appear around or circle a crystal and form a halo effect. These can actually be useful in identifying a genuine gem form a simulant as they are usually a result of crystal growth creating pressure inside the mineral. Same clarity criteria apply.
  
• Clouds - These are tiny individual crystals in groups. When a group is large and close together, they can affect the transparency of a gem.
  
• Silk - These are fibers of minerals (very very fine) within a gem. The fibers intersect at angles, generally at 60 or 120 degrees, giving it, it's "silk-like" appearance. If a gem with silk is heat treated to enhance color, the fine silk fibers will be distorted, so it can be a good thing to see as a sign of a more valuable un-treated gem. Silk is often seen in ruby and sapphire and would be the best gem examples to view for this often pretty, inclusion.
  
• Liquid Inclusions, Needles and Growth Tubes- These are long thin tubes or spaces containing gas or liquid within the stone. They come in all shapes and if there are a lot of them and especially if grouped together, will give a milk or opaque appearance. Liquid inclusions come in 3 types under GIA classifications, Single Phase: liquid only, Two Phase: a liquid and a gas and Three Phase: a liquid, gas and solid.
  
• Zoning or Banding - This shows as un uneven spread of color in the gem and can be called "growth or color bands or zoning" Generally visible with a loupe, they may not affect the beauty of a gem, but if they can be detected with the naked eye, unless interesting and thus attractive, it's generally not a good thing as your gem may show up some unattractive color zones in different types of lighting.
  
• Fingerprints - These actually look like a fingerprint or a convoluted maze. They are a result of cracks that have "healed" in part, collecting drops of liquid and sealing them. Same clarity criteria apply as for Fractures and Cracks.