I have seen Angelite and Celestite used to describe the same crystal for a long time. What inspired me to add this to my misidentification page was the fact that a vendor, who has been selling for many years was the one doing the most recent misidentifying. When I mentioned it to him, he said “Prove it!” so, here we are.
Many will say that Celestite and Angelite are the same. And in fact, they are closely related. They have the same color, this is true. Their hardness is the same. They are both sulfates. All of this is true. So it is easy to see how they could be grouped together.
Angelite is a trade name for a semi-transparent light blue-grey fine grained Anhydrite marketed as a gem material from Peru.
Anhydrite is usually formed by the dehydration of gypsum, hence the name “anhydros” meaning “without water”.
- Chemical Formula: CaSO4 Calcium Sulfate
- Crystal system: Orthorhombic
- Hardness: 3.5
- Opaque (No light can be seen through the piece)
- Variety: Nodular, polished form of Anhydrite
- Color: Anhydrite can be a pale blue to gray blue (Angelite) but can also be Colorless, bluish, blue-grey, violet, burgundy-red, white, rose-pink, brownish, reddish, grey, dark grey; colorless in transmitted light
Celestite is a trade name/marketing name for a pale to baby blue color of Celestine.
- Chemical formula: SrSO4 strontium sulfate
- Crystal System:Orthorhombic
- Hardness: 3 – 3 1/2
- Transparent to translucent
- Group: Barite group
- Celestine is normally a light blue (Celestite) but can also be colorless, yellow and tints of red, green and brown.
So while there are many commonalities between these two, there are some very specific details that prove they are not the same.