Day 92 : In work today, grading work despite it being ‘Good’ Friday. Specimens from the last open day are still out. This is some botryoidal haematite.

Day 91 : I can’t believe we are a quarter of the way through the year and this 365 project. To celebrate here is one of my favourite samples, pseudolithite. It is the one I use to throw at students who aren’t paying attention in lectures and at the TV …

Day 90 : Daphnite, a magnesian chamosite, a member of the chlorite group. This sample from the Caradon Mines, St Cleer, Cornwall. Cotton Collection, Keele.

Day 89 : Another mica, also lithium bearing, this is Zinnwaldite from the Aplite Quarry, Meldon, Devon. Cotton Collection, Keele.

Day 88 : Lepidolite, a lithium bearing mica. This is from Varuträsk in Sweden. Keele collection.

Day 87 : Bioclastic limestone from Lea Quarry, Wenlock Edge.

Day 86 : Favosites. From Lea Quarry near Much Wenlock.

Day 85: Continuing the recent zeolite theme, this is harmotome, a barium zeolite from Strontian, Scotland.

Day 84 : Scolecite (a calcium zeolite) on Stilbite (sodium-calcium zeolite). Keele Cotton Collection

Day 83 : Tourmaline, Cape Cornwall. Keele Collection.