Object of the Month:
Gypsum crystal


Jack, a Geology PhD student in the School of Geography, Earth and Environmental Sciences, describes his choice of a spectacular piece of gypsum crystal as Object of the Month at the Lapworth Museum of Geology.

Video transcript here

I’m Jack and I am a geology PhD student here at the University of Birmingham and my object of the month is this stunning piece of gypsum. Now if we take a closer look at the label we can see That it’s from a small town named Manangatang in Australia. We can also see that it’s been donated by a man by the name of M. Durbridge.

Now gypsum is the most common sulphate mineral in the world and taking a closer look at this amazing specimen, we can see two main styles of crystals: one much finer and more needle-like, and one much larger and clearer. This second type of crystal is known as Selenite.

Now this specimen will probably have formed within a void within a rock and it will have been filled with mineral rich water and these crystals need heat and space to have grown. A really spectacular case of this is the “Cave of Crystals” in Mexico and they have giant selenite crystals up to 10m big.

Because of the really fine texture of the needle-like crystals, we’re actually getting some sand particles trapped amongst them. This is giving it this kind of pink tinge. You can see it trapped around some of the larger crystals as well.

As you can see here at the Lapworth Museum at the University of Birmingham we’ve got some really spectacular crystals and minerals and I’d recommend anyone to come and see them, and come and check out my object of the month.