What Does Fluorite Look Like?

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When it comes to identifying fluorite it can often be a bit difficult due to the visual nature of the mineral looking much like other minerals.  Many minerals will look like a crystal and have some similar colors, and fluorite is definitely one of those minerals

One of the nice things about identifying fluorite is that it does have a distinguishable look that can really help set it apart from other minerals.  Once you see or handle a few specimens of fluorite you will get a good idea on what to expect when you come across it in the future.

Many specimens of fluorite are often used for display and can also be carved out into shapes.  Fluorite is the very definition of 4 on the Mohs scale of hardness.  This makes the mineral not too soft and not very hard and allows the ability to work with the mineral.

Key Visual Looking Characteristics of Fluorite

When you identify fluorite there are some visually distinguishable features that can really help out.  Even the fluorite specimens that have been cut into shapes can have some common features you can easily recognize.  You can visually identify fluorite by its following looks:

  • It’s color:  Much of fluorite sold today as a specimen will have that notable lighter green color.  Fluorite will also have colors of purple, gold yellow, pink, blue, gold brown, and also colorless.
  • It has translucency:  Though not always clear of inclusions within it, fluorite will look like glass with some ability to see into it.  Its glassy translucency is one of its very distinguishable characteristics even in raw uncut form.
  • The crystal shape:  Crystal shape can be a bit of a difficult identifier for a lot of fluorite.  Some fluorite crystals will have nice 6 sided crystal shapes, which are not usually a uniform cube (more like a rectangular cube), but very distinguishable.  Many other forms of fluorite can be chunks of glass like crystals that are conglomerated together in a large specimen.
  • It’s ability to fluoresce:  Fluorite can fluoresce in a variety of brilliant colors; blue, red, purple, green, yellow, and even white.  To see these fluorescent colors you need a short or long wave UV light source. 

The best and helpful identifiers for fluorite will be its glassy translucent appearance with that nice lighter green color about it.  When you also see the purple swirling around within the specimen as well, it can be an easy give away that it is fluorite.

Most of the favorite specimens of fluorite I see today are the mix of greens and purples (as an obelisk for that matter).  This very combination in color can quickly trigger the thought of “fluorite” for many rock and mineral enthusiasts. 

It’s some of the other not as common colors that can throw off people in identification.  That’s when some of the other identifiable features can come into play. 

Green Fluorite Crystals: These are deeper green fluorite crystals still attached to its host rock. The crystals have translucency and have the identifiable cube or square shape crystals.

   

Fluorite Varieties and Their Different Looks

Fluorite does not really have any “named” varieties.  Much of the variety of fluorite will be distinguishable by its color.  There are some varieties of fluorite that are very common and some that are not seen very much.  Some different looking fluorite varieties will include:

  • Green Fluorite:  This is the most popular type of fluorite.  It can come in that conglomerated look or be on a nice matrix with very distinguishable green crystals.   
  • Rainbow Fluorite:  This green and purple mix of fluorite is a favorite for many.  This form of fluorite is the most notable and often cut into obelisks and other shapes.  
  • Pink Fluorite:  Is less common and not as easily identifiable.  Some nice natural deep pink fluorite specimens can be quite expensive to obtain.
  • Purple Fluorite:  This is as it sounds, the color is purple.  Some nice purple specimens will be in crystal form.

Much of the varieties of fluorite will be relatively cheap.  Many specimens can be quite easy to obtain and are usually appealing to the eye.  However, when it comes to some nice crystal specimens, even still attached to their host rock, those prices can be much higher.

Rainbow Fluorite: This type of fluorite, expressing the swirling purples and greens, is a favorite among rock and mineral collectors. This variety of fluorite is often cut into obelisks and other shapes.

Different Things to Look for Between Fluorite and Quartz

It can be very difficult to identify the difference between fluorite and quartz.  Both can appear to be quite vitreous and express some transparency.  Essentially, they can look the same.  It is not uncommon for many to identify the two incorrectly.  Some visually differences to look for between fluorite and quartz are:

  • Fluorite crystals are isometric:  This means that fluorite crystals are equal in all three dimensions.  So fluorite can be in the similar shape of a cube, its corners will have 90 degree angles on its three dimensions.  Quartz crystals will be longer with six hexagonal sides and a point.  This is the most visually identifiable difference between fluorite and quartz crystals.
  • Fluorite is not as hard as quartz:  Though not always a great way to visually identify between the two, fluorite is a bit softer than quartz.  You can scratch the surface of  fluorite with steel, but cannot do the same for quartz.
  • Fluorite has the green and purple variety:  One of the more popular varieties of fluorite is the swirling cloud-like green and purple variety, sometimes called rainbow fluorite.  Quartz does not have this quality, unless maybe, it is manufactured in this way. 

Sometimes fluorite and quartz are not in good visual crystal form.  This  can make it fairly difficult to determine what you have.  A scratch test with a steel knife might be the next best way to help you identify what you have.

Amethyst is a type of quartz.  It being purple, is what defines it as amethyst.  Since flourite can be purple as well, we quickly see how difficult it would be to tell the difference.  This is where scratch tests and other non visual ways can help you identify whether you have fluorite or quartz.

There are many out there that mislabel fluorite for quartz and vice versa.  Very often you see crystal “chips”, or broken up pieces, of purple and green fluorite being sold or labeled as quartz.  When in fact they are fluorite. 

Different Things to Look for Between Fluorite and Calcite

Fluorite and calcite are two minerals that can be similar in appearance.  These two minerals do have some identifying differences that set them apart though.   Some visual differences to look for between fluorite and calcite are:

  • Fluorite crystals are isometric:  This means that fluorite crystals are equal in all three dimensions.  So fluorite can be in the similar shape of a cube, its corners will have 90 degree angles on its three dimensions.  Calcite crystals will be longer trigonal type crystals.  Calcite crystals can come in a few different looking patterns and can even look like it is in thin, square, layering sheets.  
  • Fluorite has translucency:  While many crystals of calcite can have translucency as well, fluorite is quite distinguished by this characteristic.  There are lots of calcites that will lack translucency.
  • Fluorite has a smaller range of colors.  Fluorite has some nice colors like green and purple.  However calcite, even though its most popular colors are in white and clear, can have pretty much any other color including orange, red, black, and gray. 
  • Calcite can have banding while fluorite does not:  I have seen many specimens of calcite, such as zebra calcite, that have banding.  Fluorite may have some contrasting colors within it, but no banding. 

The best ways I have found to determine if I have fluorite or calcite has been mainly the color.  Most flourite people are selling is that light green or the combination of the green and purple.  Seeing that translucency really helps as well.

Much of the calcite samples I have seen, that are not in crystal form, are loose chunks that have a shiny surface that has no translucency.  Many calcite examples will almost look like shiny wet soap, or I have even heard shiny fake plastic looking rocks.

Different look between Fluorite and Calcite: On the left is some raw fluorite, and on the right is some calcite. Aside from the difference in color, it can be hard to visually distinguish which is fluorite and which is calcite. We can also note that the fluorite expresses some translucency and the calcite does not.

Conclusion

When it comes to identifying fluorite always think lighter greens and that combination of green and purple.  Those are the popular and favorites.  

Incidentally, don’t forget to add the appearance of some translucency.  Some specimens of fluorite are very translucent while others not so much, but it is there.

As I always say with identification of minerals, it is always nice to see several examples to help me be able to identify them in the future.  I hope the pictures in this article can help you with that.

For some more information about fluorite you can access my article here; “All About Fluorite”.  If you are looking for some more pictures and in depth specs on fluorite, I like what they have showing over at Wikipedia (Fluorite).

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