Halite – Day 23 of the Mineral Advent Calendar

This holiday season, why not get a mineral every day instead of chocolate? Today’s mineral is Halite find out more about it below..

It’s December 23rd and if you have finished work and are lucky enough to have tomorrow off, you might now very be….

If so, please be safe when driving back; if the rest of the country is anything like Devon tonight the roads are pretty wet!! Fortunately (or not, depending on how much rain you get) that means we probably won’t see any of a mineral that is usally EXTREMELY common this time of year – no not Ice, but it’s related – that is rock salt, used in grit to keep the roads safe. Salt is most definitely a mineral, as anyone who has ever been to a salt mine can attest. Rock salt, more properly called Halite when in it’s mineral form, is something that although we may be more familiar with it on the kitchen table, it is essential for safe driving at this time of year. So stay safe on the roads if you are driving home tonight, and check out this amazing microscope image of a Halite crystal taken by Dr Natasha Stephen in Plymouth University Electron Microscopy Centre.

A lovely Halite crystal photograph taken by Dr Natasha Stephen at the Plymouth University EM centre.

A lovely Halite crystal photograph taken by Dr Natasha Stephen at the Plymouth University EM centre.

Halite:
Chemical formula: NaCl
Colour: Colourless, white, yellow, red, purple or blue
System: Isometric
Hardness (Mohs):
Can you find it in the UK? Er yes! (In fact it is still mined in Cheshire)

Cheshire's salt mines are still very much active! Image from the BBC.

Cheshire’s salt mines are still very much active! Image from the BBC.

Halite is a common mineral all over the world and although I have been talking about it in it’s mineral sense (that can be mined – a type of mineral called an evaporite), let’s not forget that you can also get halite when it is exsolved out of sea water! This can cause Halite to crystallise in sheltered spots around the coast, so keep an eye out for these little white-pink cubes, you may find it more easily than you think!

For more information about Halite please visit the MinDat website.

Galena – Day 22 of the Mineral Advent Calendar

This holiday season, why not get a mineral every day instead of chocolate? Today’s mineral is Galena find out more about it below..

We are getting towards the end of the Mineral Advent Calendar now so your final preparations for a couple of days filled with family, friends and celebrating must be nearly done. Today is the Winter Solstice, so if you have been celebrating already then Happy Midwinter!! There are many things that you can use to celebrate the time of year, but one of my favourites is crackers, and crackers depend on one thing to make them go bang!

Do you have your crackers yet?

Do you have your crackers yet?

And that one thing is silver fulminate. It’s the chemical used on the strips of crackers that makes them pop as you pull them apart, a delightful mini-firework for your kitchen table! In order to get silver you mine it directly (as in Day 11) or you can mine something with a lot of silver in it, and that is our mineral today – Galena!

A lovely big lump of Galena from Dakotamatrix.com. But the best identifying feature of Galena is it's density - it's unusally dense!

A lovely big lump of Galena from Dakotamatrix.com. But the best identifying feature of Galena is it’s density – it’s unusally dense!

Galena:
Chemical formula: PbS
Colour: Lead-grey
System: Isometric
Hardness (Mohs):
Can you find it in the UK? Yes

Ok I’m starting to think this is my computer now, so as soon as I can get a version of the map to work I will upload it, but needless to say you can find Galena in the UK, to find out where check the locations list on the MinDat website.

For more information about Galena please visit the MinDat website.

Graphite – Day 21 of the Mineral Advent Calendar

This holiday season, why not get a mineral every day instead of chocolate? Today’s mineral is Graphite find out more about it below..

The second of the UK snail-mail deadines fell today and sorry, if you missed the 1st class post today, then your only option you have to get deliveries done by the 25th is Special Delivery. But in relation to Saturday’s post, you need to get your scissors flying to make the mail!!

Sharp scissors are essential for nice wrapping!

Sharp scissors are essential for nice wrapping!

But apart from iron, you need carbon to make the best steel scissors! The easiest place to get carbon, although it is a common element (an ingedient in many minerals) is Graphite. So our second Mailing Mineral is Graphite! Graphite is also helpful if you want to make sure you have sent all the seasonal cards on your list by checking them off with your pencil!

Lovely graphite crystals taken by  John Jaszczak.

Lovely graphite crystals taken by John Jaszczak.

Graphite:
Chemical formula: C
Colour: Iron black to steel-grey
System: Hexagonal
Hardness (Mohs): 1 – 2
Can you find it in the UK? Yes

The only graphote location map I could get to work! From the MinDat website.

The only graphote location map I could get to work! From the MinDat website.

Unfortunately the map showing locations you can find Graphite in the UK isn’t really working, but you can find graphite in all the places where you can find metamorphosized rocks that are rich in carbon, so check all the usual mineral rich locations (Cumbria, North Wales, Cornwall, North West Highlands).

For more information about Graphite please visit the MinDat website.

Nahcolite – Day 20 of the Mineral Advent Calendar

This holiday season, why not get a mineral every day instead of chocolate? Today’s mineral is Nahcolite find out more about it below..

The party season is defnitely upon us, and if you had a big night last night, or are planning one over the next few days, to deal with all the rich food and drink you may find yourself reaching for an antacid. But have you ever stopped to think what is in an antacid?

If you had a big night last nigt, you might have needed one of these this morning! (image from The Principles of General Chemistry)

If you had a big night last nigt, you might have needed one of these this morning! (image from The Principles of General Chemistry)

Well one of the main ingredients is sodium bicarbonate, something that you may be familiar with from the kitchen, but did you know it can also be found down a mine as well? Yes sodium bicarbonate comes from the mineral Nahcolite. The sodium bicarbonate in Nahcolite is a natural pH neutraliser, which makes it excellent for those upset stomachs we can all get at this time of the year. Obviously sodium bicarbonte can also be used for baking, but if you are feeling a bit squiffy then probably the mention of cookies and cakes won’t help you right about now!

Nahcolite mineral lump - kinda looks like a snowball right? Probably the closest we will get this December (sigh)

Nahcolite mineral lump – kinda looks like a snowball right? Probably the closest we will get this December (sigh), image form Wikipedia

Nahcolite:
Chemical formula: NaHCO3
Colour: Colourless, white, greyish
System: Monoclinic
Hardness (Mohs):
Can you find it in the UK? No

Nahcolite is not found in the UK as far as I know, but again, if I am wrong – please let me know in the comments section!

For more information about Nahcolite please visit the MinDat website.

Haematite – Day 19 of the Mineral Advent Calendar

This holiday season, why not get a mineral every day instead of chocolate? Today’s mineral is Haematite find out more about it below..

It’s the 19th of December, so you know what that means – it’s the last posting day for second class postage to reach it’s recipient before the 24th. So you have probably had those scissors out doing all your wrapping and sticking over the last couple of days. But don’t worry if you missed the 2nd class post today – you still have the first class post – until Monday!

Sharp scissors are essential for nice wrapping!

Sharp scissors are essential for nice wrapping!

However, in order for your beautifully wrapped presents to have been wrapped, you need nice scissors, preferably sharp steel ones – and for steel scissors you need iron, found in the ore Haematite (yes I know some people spell it Hematite, but I was brought up to include the ‘a’, so I look at it the same way that colour is spelt WITH a ‘u’).

A gorgeous photo of haematite by Jean-Marc Johannet from the MinDat website.

A gorgeous photo of haematite by Jean-Marc Johannet from the MinDat website.

Haematite:
Chemical formula: Fe2O3
Colour: Steel-grey to black in crystals and massively crystalline ores, dull to bright “rust-red” in in earthy, compact, fine-grained material.
System: Trigonal
Hardness (Mohs): 5 – 6
Can you find it in the UK? Yes

Unfortunately the map showing locations you can find Haematite in the UK isn’t working, but needless to say it is a fairly common mineral easily spotted by it’s rust red colour when it has been weathered.

For more information about Haematite please visit the MinDat website.