Six different types of Amethyst are Purple Amethyst, Cape Amethyst, Pink Amethyst, Mossy Amethyst, Ametrine and Prasiolite. The first four are related to the shade or form of the Amethyst crystal, and are all 'true' Amethysts. The last two are closely related to the Amethyst gemstone but are different varieties.
These are not the only types of Amethyst crystals, there are others such as Auralite, Brandberg Amethyst and Cactus Quartz. There can also be a few synonyms for the same type of Amethyst crystal, for example Cape Amethyst is also known as Chevron Amethyst.
Note that many names in the gemstone industry are 'trade names' or common names given to a particular shade (e.g. Pink Amethyst) or source of a gemstone (e.g. Siberian Amethyst), however in gemology (the study of gems / precious stones) there is only one scientifically correct name i.e. "Amethyst".
1. Purple Amethyst
Purple Amethyst is the traditional Amethyst stone everyone knows in the dark purple color, and the deeper the color the more valuable the gem.
Amethyst is a type of quartz and is found on all continents. Traces of iron and manganese give the stone its purple hue.
Shades can range from pale lilac through lavender and mauve to deep violet. This is the pure, high grade Amethyst used in fine jewelry.
2. Cape Amethyst
Cape Amethyst is a mixture of Amethyst and white Milky Quartz.
The Milky Quartz can be quite feint or in distinct layers.
When the Milky Quartz is in layers it is often called Banded Amethyst or Chevron Amethyst.
Chevron Amethyst or Dog Tooth are both terms used when the white bands are in a triangular pattern.
It is named after the Cape region in South Africa where the best specimens are found.
3. Pink Amethyst
Pink Amethyst was first discovered in Argentina and can have soft lilac to deep pink and even peachy tones.
The inclusion of the Hematite mineral causes the Amethyst deposit to form as a pinkish crystal instead of purple. Hematite typically produces red streaks in most stones.
Another Amethyst that has reddish edges or spots due to Hematite is Auralite (23) found in Ontario, Canada, also known as Canadian Amethyst.
4. Mossy Amethyst
Mossy or Moss Amethyst are Amethyst crystals with thin vein like structures and tend to be more reddish overall.
The internal threads or branches are usually black tourmaline inclusions and so it is also known as "tourmalinated" Amethyst.
Sometimes the tourmaline is present as small flecks and not as strands.
When Amethyst quartz is heated it transforms to yellow Citrine quartz and can produce a bi-color effect of both purple and yellow hues in one stone.
Ametrine is derived from the words "amethyst" and "citrine'.
In some Amethyst deposits geological heating has caused this process to occur naturally, however Purple Amethyst can also be heated manually in a lab to produce the same effect.
If there is a distinct line between to the two colors this can indicate manual heating but a gradual color change can indicate natural Ametrine.
Green Amethyst is more correctly called Prasiolite and is a very pale green variety of quartz.
This gemstone usually occurs naturally near stable Purple Amethyst deposits. High temperature lava flows or intrusions would have caused chemical reactions that transformed the purple quartz into green quartz.
This heating process can be simulated in a lab by heating or irradiating Purple Amethyst. These crystals are most likely what you will find in Green Amethyst jewelry, as naturally occurring Prasiolite is very rare.
So, in conclusion these are some of the different kinds and colors of the amethyst gemstone. They range in color from the traditional Purple Amethyst, as well as Pink and Green Amethyst. Then there are varieties mixed with other minerals such as the banded Cape Amethyst, multi-colored Ametrine and included Toumalinated Amethyst.
As you may know Amethyst is the gemstone for February so if you already have a collection of the traditional purple Amethyst, these are some other types to collect or to gift to someone with a birthday in February. It is quite difficult to pick one but I think I quite like the Chevron Amethyst - I have seen some stones with a very clear chevron pattern which is quite striking. Let us know in the comments which is your favorite type of Amethyst. *Mandy.