Water Soluble Gems
There are a number of gems that are water soluble to some degree. These vary from Celestite that is very slightly water soluble to Villiaumite that is more readily soluble in water. There are a few, such as Boracite, that don’t dissolve in water but slowly decompose. The more soluble of these “water soluble” gems pose a special challenge to the gem faceter. Other liquids, such as alchohol, must be used when polishing these gems. Villiaumite is probably the most challenging gem to facet with regard to water solubility. In addition to being water soluble, Villiaumite is also poisonous. There are many other minerals that are also water soluble but rarely faceted. Many gems are soluble in carbonated water or various types of acids. These gems are not listed since acids and carbonated water are not used in the faceting process.
For the most part, gems that are very slightly to slightly soluble in water require little to no special care when properly stored. Most gem collectors don’t even realize that these gems are water soluble at all. All gems should be kept in a dry environment. There is also a gem that could be considered the opposite of a water soluble gem. Some Opals may be prone to “drying out” since they may contain up to 10% water.