07 April 2015

Tuesday is drawing day - last week at Natural History Museum

Perhaps the Natural History Museum isn't the best place to go during school holidays. As there's a security check (so-called) on entering, there's a long queue snaking its way forward outside, and it took half an hour to get in -
Near the minerals gallery some volunteers had a trolley of minerals, most of which I couldn't identify, even though I worked for two years in a geology library! (550 is the Dewey category for earth sciences.) (In case you ever need to know.)
Magnetite, haematite; fluorite, quartz;
granite, feldspar, gypsum, rose quartz;
pyrites in a matrix, calcite; apatite
The "handling sessions" are A Very Good Thing, being able to feel the texture, the weight, of the object. Once in the gallery I kept an eye out for these "new mineral friends" - this case, for example, contains different types of calcite -
including these two clear masses, both from Iceland -
Before drawing could start, there was a lot of looking. The information on the labels is written in specialist language, which is refreshing - no dumbing down in this venerable arrangement, in these splendid cases, numbered and categorised -
At the end of the gallery, this look-up table, listing all the minerals and where they can be found -
The azurite contained wonderful colours (it was ground up to use as a pigment) -
 and next to it was hydrozincite, a mineral of lumps and bumps, including the speciment with botryoidal masses -
 More wandering around, in the volcanic displays, found some bits of pumice from the eruption of Krakatoa in 1883 that floated from Sumatra to Kenya, and a rock (er, that's a dacite 'blast facies') from the first moments of the eruption of Mount St Helens in 1980, and also this 'lava foam' pumice, which reminded me of the inside of bone -
Another amazing specimen was a slab of komatite - lava formed at 1650 degrees C - it's only found in the oldest rocks, those more than 2,700 million years old.
The spinifex texture of komatite (via)
Having got up close to the apatite prism, and the calcite, I was delighted to find more apatite, of various colours, on calcite, and beside them an odontolite - fossil turquoise - antelope tooth (but did I think to photograph it? no).
A gathering of minerals
The gallery got very busy, but no one else showed up to draw -
On the way out there was a convenient seat right beside the moa skeleton - an extinct flightless (indeed, wingless) bird whose bones were found in New Zealand -
... it called out to my pen -
and on closer inspection revealed that it had some tail bones, and a third toe on each foot (of course).  

1 comment:

Felicity said...

I had such a good time in the Natural History Museum - so many fascinating things everywhere you looked. And in spite of my initial scepticism, I was mesmerised in the Minerals Gallery.

The moa looks like a supersized emu - you would not want of those stealing your picnic!