Feldspars are popular because they are one of the most abundant minerals on Earth. They are present in a variety of habits and are found in a tremendous array of environments and there are many collecting sites where good feldspar crystals can be found. Some collectors focus strictly on feldspars – there is enough variety to keep even a collection of thousands of feldspars exciting. Still, they are not tremendously popular, because with the exception of a few kinds like microcline var, amazonite and labradorite, they are not terribly colorful.
Most feldspar crystals are white to peach in color. Still, this should not be a deterrent to the collector. The beauty and structural complexity of feldspar crystals makes up for their lack of color. Also, considering they are found in many geological environments, they may be associated with many colorful minerals. There are also many varieties of feldspar that are great for ornamental carving and some kinds that can be faceted. Feldspar has a high hardness of 6 to 6 ½ so it can be used in jewelry without risk of being fractured or chipped easily. Labradorite and oligoclase var. sunstone are especially popular in jewelry for their color changing Schiller effect. With the exception of amazonite specimens which are pricy due to their amazing colorm feldspar specimens are inexpensive. They are likely far cheaper than specimens of minerals that are near equally as common such as quartz or calcite. This makes it easy to start a collection of fine feldspars if you don’t want to go into the field and search for them yourself!
Feldspars are one of the most underrated collectable minerals- learning to understand them and appreciate them reveals many secrets about the inside of the Earth. Geologists can use feldspars to easily determine the temperatures and pressures at which rocks form and what their chemistry is. They can also use radioactive isotopes in feldspars, particularly potassium and argon to determine how old rocks are that contain them. They are certainly a mineral that deserves a lot of appreciation!