Is it Blue Calcite or Celestite?

How to Tell Blue Calcite and Celestite Apart 

...once and for all. 

If you saw my recent post about Common Crystal Mix-Ups, you saw that I hate when there's confusion between blue calcite and celestite - because they can be easy to tell apart, once you know what to look for!

In this post, I'll tell you how to tell the two apart, so you never have to deal with this mix-up again!

Blue Calcite


How DO you tell blue calcite from blue celestite? 

If you're not sure what to look for, it can seem daunting to tell these two apart. 

First, let's look at the similarities: 

  • They are both (typically) from Madagascar 
  • They are both a pretty light blue 
  • They are both pretty soft minerals: about a 3 on the Mohs scale

But that's where the similarities (mostly) end. Here are the main differences: 

  • Blue calcite only grows in massive: never crystals. Celestite does grow in massive form (or may be polished down so that you can't see the crystals); but it's almost always sold as a geode or other "crystal" form. 
  • Celestite will usually be on a matrix (which is what the crystals grow on). Blue calcite almost never has matrix (since it grows as masses, it doesn't need matrix). Even raw chunks will have minimal or no matrix. 
  • Because of this (above), blue calcite is always either polished (palm stones, spheres, flames, etc.) or in raw chunks. Celestite is typically available in geode form or gently polished: the matrix (what the crystals form on) is polished into a freeform, heart, or sphere around the crystals.
  • Celestite is more translucent. Blue calcite is opaque. 
  • Blue calcite is almost always more affordable (by size/weight) than celestite. 
  • Blue calcite often has white veins throughout the mass. Celestite does not: it is just blue crystals on (a typically grey) matrix Note: sometimes, the crystals can be near-transparent or so light they look almost white - or the grey matrix can be very light - but there should be no white veining throughout the stone. Blue calcite will always contain regular veining/marbling throughout.

Keep practicing!

So there you go! A full run-down on exactly how to tell the difference between blue calcite and celestite. 

Keep practicing and looking at difference pieces - and you'll be able to tell them apart easily in no time.