Dog tooth calcite mineral specimens found in Somerset, UK. Calcite is a very common mineral with just as many different variations and colours, it is highly reactive with many acids (such as hydrochloric acid) including weaker ones, which will make the calcite bubble and 'fizz' when the two come into contact with each other. Known to be fairly soft, it is quite low on the moh's scale of hardness at 3. Dogtooth calcite is found in open spaces such as limestone caves, geodes and veins, that consists of large calcite crystals thought to resemble dogs' teeth due to the 'pointed' crystal habit they form in. Popular among collectors, UK specimens of dog tooth calcite are increasingly becoming harder to find. These specimens from Somerset tend to form in crystal beds where the crystals form mostly all pointing the in the same direction, as opposed to the random directions that the Cumbrian dog tooth calcites form in.