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.
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.