X Close

UCL Culture Blog

Home

News and musings from the UCL Culture team

Menu

Fun with Minerals 2: Back in the Habit

By Subhadra Das, on 15 September 2016

UCL Earth Sciences student and veteran of UCL Geology Collections curation Nadine Gabriel returns with another guest blog relating her work with the mineral collection over the summer. It’s great to have her back and to demonstrate that collections management is clearly habit forming.

Hello, it’s Nadine Gabriel again and I’ve been spending another summer working with UCL Geology Collections. Since the Rock Room will soon have another home, I’ve been removing minerals from display cabinets, auditing the collection and accessioning some new specimens. Once again I have seen thousands of minerals and one thing that always catches my eye is the wide variety of habits, so I thought this topic would make a great sequel to my first blog.

A mineral habit is the shape of a single crystal or group of crystals. This is dependent on a mineral’s crystallographic system (the atomic arrangement of a crystal) and its growing conditions. The basic habit classification is defined by how well-formed a crystal is. A mineral is euhedral if all faces are well-developed, which means it grew in uncrowded, optimal conditions. However, if a mineral grew in unsuitable conditions, it becomes subhedral (some faces present) or anhedral (no faces). Below are the more specific habit classifications.

First up is the massive habit which contains no visible crystal structures, but don’t assume that this doesn’t make them less eye catching! Many beautiful minerals such as deep blue lapis lazuli and vivid red (but poisonous) cinnabar have this habit.

Minerals with cubic habit

Cubic: pyrite, fluorite and galena (top). Hexagonal: quartz (middle left) and aragonite (middle right). Platy: biotite (bottom left) and talc (bottom right)

(more…)

How to make a diamond

By Jack Ashby, on 28 October 2015

This is a guest post from our artist in residence Eleanor Morgan. It is part of a series exploring the exhibition Glass Delusions at the Grant Museum of  Zoology.

Diamonds made from the dead creatures of the River Thames (c) David Dobson

Diamonds made from the dead creatures of the River Thames (c) David Dobson

This year, on Thursday the 30th of July, I made a diamond. Only a few weeks before, this diamond had been floating around the River Thames in the form of dead plants and animals. It had taken a few hours, high pressure and temperature and most importantly a lot of help from UCL chemists and geologists to transform the dead creatures of the River Thames into tiny diamonds. These can now be seen at the Grant Museum as part of my exhibition Glass Delusions, along with a booklet ‘How to make a diamond’ which describes the process. (more…)

Fun with Minerals

By Nick J Booth, on 8 October 2015

This is a guest post by Nadine Gabriel, a UCL student and volunteer with UCL Museums. All photos by the author.

Hello there, I’m Nadine Gabriel and I’ve been working with the UCL Geology Collections for just over a year. Towards the end of the summer holidays, I was given the chance to audit the thousands of mineral specimens in the Rock Room to ensure that we have a record of what is (and isn’t) in the collection. While auditing the collection, I handled a wide variety of specimens and learnt about new minerals and their classification – I’ve come across so many minerals that I’ve never heard of, even after doing two years of geology. But the best thing about working with the collection was saying ‘ooh’ and ‘ahh’ every time I saw a nice shiny mineral.

Heart Minerals - calcite and malachite.

Heart Minerals – calcite and malachite.

When I first started working with the geological collections, my audits involved working with Excel spreadsheets and paper catalogues filled with entries from way before I was born. (more…)