back to top of - eclectic  jewelry pages

What are agates?

Agates are micro-crystalline quartzes within the chalcedony family of micro-quartzes. There are multitudes of names for types of agates. Names vary depending on geographic origin, coloring, special banding effects, and other characteristics.

What are the different types of agates?

Raw agates are found in three main forms: amygdaloid, lithophysae, and sedimentary. Amygdaloid agates resemble almond shaped beat up potatoes. Lithophysae are more commonly called thundereggs and have a ridged or bubbly texture. When cut, the middles often have a star shaped center cavity. Sedimentary agates have a smoother cauliflower like texture than the other two agate types. These three agate types are all nodules, which are solid. Geodes are hollow nodules that can be any of the three types of agate.

What is the difference between jaspers and agates?

Jaspers can often be confused with agates since they are both types of micro-crystalline quartzes. Agates fall into the fibrous chalcedony group and jaspers fall into the grainy chalcedony group.

What are the kinds of chalcedony?

Chalcedony gems are: agate, carnelian, chrysoprase, onyx, plasma (fibrous), sard, bloodstone, chert, jasper, and plasma (grainy).

What are the colors of agates?

Agates come in many natural colors depending on what minerals are embedded in the main material of the agate, which is silica. Super bright colored agates are most likely dyed. Some agates have even been dyed to look like onyx. There are iridescnt agates as well. They are rarer than other types. They can be used as a less expensive alternative to opals.

Is there such a thing as fake agates?

Interestingly, there are some types of non-agate agates. That is material that has banding and coloring effects that look like agate but are not made from silica. Rainbow silica and Fordite (aka Detriot Agates) are two types of non-agate agates.

Agate Types Based on Physical Characteristics

Agate Types Based on Location

Here is my list of agates named after the places they were found. This list is still evolving and will be updated as I find new ones to list.