Category Archives: Geology

Uraninite – Day 12 of the Mineral Advent Calendar

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

As we move towards the 25th of December, the number of shopping days decreases – and you might be out searching for the perfect gift! Sticking with the vintage holidays you might decide to get a vintage festive gift for a friend or loved one and when shopping in antiques stores or vintage fairs there is one thing that is often hard to miss, and that is the lurid yellow-green glassware often called Vaseline Glass (due to it’s similarity to the jelly).

One of the key giveaways about Vaseline Glass (or Uranium Glass) is that it is a bright yellow-green and fluoresces in UV light (image from 1st glass 1st things).

One of the key giveaways about Vaseline Glass (or Uranium Glass) is that it is a bright yellow-green and fluoresces in UV light (image from 1st glass 1st things).

However the interesting thing about this glass and the reason it is such a bright colour, is that it was made with the radioactive element uranium (leading to it’s other name – Uranium Glass), and the uranium came from the mineral Uraninite (also called Pitchblende). Don’t worry – the level of radioactivity is so low that it is generally considered harmless, and some people love to collect this glass for it’s historical value – so it could turn out to be an interesting talking point as a gift for that vintage lover in your life!

 

Bright yellow Uraninite from Wikipedia

Lovely yellow-green Uraninite from Wikipedia

 Uraninite:

Chemical formula: UO2
Colour: Black, brownish-black, greyish, greenish; green-gray (thin fragments)
System: Isometric
Hardness (Mohs): 5 – 6
Can you find it in the UK? Yes

You can find Uraninite in a few locations across the UK, but it is more often found in it's grey-black form.

You can find Uraninite in a few locations across the UK, but it is more often found in it’s grey-black form (from the MinDat website)

Although the radioactive element of Uraninite is not generally often high enough to be dangerous, it is always wise to take precautions with any radioactive mineral. To find out more about the safe handling of radioactive minerals please check this site!

For more information about Uraninite please visit the MinDat website.

Silver – Day 11 of the Mineral Advent Calendar

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

Back on the vintage theme, if you decorated your tree you probably used tinsel, but instead of the multi-coloured garlands we think of today, until fairly recently, tinsel was the thin strands of shiny material you would drape all over the branches like hair!

This metal tinsel was probably made from lead, but in the 1600's tinsel was made from actual silver! This image is from Motherboard.

This metal tinsel was probably made from lead, but in the 1600’s tinsel was made from actual silver! This image is from Motherboard (originally from Ebay, but the listing has gone).

Using tinsel to decorate has been something that we have been doing for hundreds of years, but instead of the plastic types we think of today, tinsel used to be made of thin metal strips – and back in the 1600’s when tinsel was first used, it used to be made of actual silver (obviously this wasn’t decoration for the masses). And you can see, why – it’s very tinsel-ly just naturally. Though I imagine it tarnished pretty fast!

This silver is very tinsel-like. The photo was taken by Ian Jones.

This silver is very tinsel-like. The photo was taken by Ian Jones.

 Silver:

Chemical formula: Ag
Colour: Er, silver?!
System: Isometric
Hardness (Mohs): 2½ – 3
Can you find it in the UK? Yes

Locations for Silver in the UK from the MinDat Website - again visit the website for much more detailed information.

Locations for Silver in the UK from the MinDat Website – again visit the website for much more detailed information.

You can find Silver in the UK, though usually in very small amounts. It tarnishes out to a black-grey and is often found in places where other commercial minerals (like lead) have been mined, for instance in Cornwall, Wales or Cumbria.

For more information about Silver please visit the MinDat website.

Kaolinite – Day 10 of the Mineral Advent Calendar

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

So if you have friends who live overseas you will surely have today and the next few days marked on your calendar, as it’s the LAST POSTAGE DAY FOR AUSTRALIA AND NEW ZEALAND  today. Unfortunately you have already missed Africa; the Middle East; Asia Central and South America; and the Caribbean (among a few others), but for most other locations you still have a few days left to get your mail delivered before the 24th December.

Is your overseas post ready to go - or have you already sent it?!

Is your overseas post ready to go – or have you already sent it?!

If you are posting a letter to a loved one or friend, did you think about the fact that your festive envelope couldn’t exist without the mineral Kaolinite? A clay mineral, Kaolinite is added to paper to improve the texture and as a filler, a practice which has been done for years!

A gorgeous Kaolinite crystal (image from Wikipedia)

A gorgeous Kaolinite crystal (image from Wikipedia) – EDIT: As DB correctly noted this isn’t just Kaolinite, but Kaolinite that has replaced a lovely feldspar crystal, but kept the shape (known as a psuedomorph). For an image of just Kaolinite crystals, see the MinDat page here.

 

 Kaolinite:

Chemical formula: Al2(Si2O5)(OH)4
Colour: White to cream and pale-yellow, also often stained various shades of brown
System: Triclinic
Hardness (Mohs): 2 – 2½
Can you find it in the UK? Yes

Kaolinite is found in many locations in the UK, in fact if you zoom in on this map from the MinDat Website you can see more and more little crystals pop up!

Kaolinite is found in many locations in the UK, in fact if you zoom in on this map from the MinDat Website you can see more and more little crystals pop up!

Kaolinite is often known by another common name of China Clay. If you think where in the UK you can find China Clay Quarries – that is undoubtedly where you can find Kaolinite. Finding a lovely crystal like the one in the images is much harder, but if you do you should treasure it!

For more information about Kaolinite please visit the MinDat website.

Muscovite – Day 9 of the Mineral Advent Calendar

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

Continuing on the theme of a vintage holiday season, another of my favourite things about this time of year is how much everyone embraces the sparkles!

Even my nails like to be sparkly at this time of year!

Even my nails like to be sparkly at this time of year!

In fact our love of sparkles isn’t a modern thing, even the Victorians like to embrace the glitter! But not having access to the plastics that we take for granted to make our sparkles, they had to look elsewhere, and found the amazing mineral Muscovite Mica. During the Victorian period, wealthy poeple celebrating the season would buy chunks of this mineral and then break it up to use the little reflective flakes as glitter, and if you have even been into a lab after a first year geology student has been doing their mineral identification – you will know that it still happens!! So today’s mineral is Muscovite Mica – vintage glitter.

Muscovite MIca from the MInDat website, image taken by Rob Lavinsky and irocks.com

Muscovite Mica from the MinDat website, image taken by Rob Lavinsky and irocks.com

 Muscovite:

Chemical formula: KAl2(AlSi3O10)(OH)2
Colour: White to colorless, silvery-white, and tinged various colors by impurities.
System: Monoclinic
Hardness (Mohs): 2½
Can you find it in the UK? Yes

Muscovite Mica can be found in many places across the UK, not least as part of some sparkly or shiny rocks that you might spot. This is the locations of Muscovite in the UK from the MinDat website.

Muscovite Mica can be found in many places across the UK, not least as part of some sparkly or shiny rocks that you might spot. This is the locations of Muscovite in the UK from the MinDat website.

Mica is a common mineral that makes up many types of rock – you may be familiar with the dark brown to black version of Mica – Biotite – that you can see sparkling away in lumps of granite. Muscovite mica is also most easily found whe you look at a rock, rather than as big lumps of crystal, but you can still find it across the UK.

For more information about Muscovite please visit the MinDat website.

Quartz – Day 8 of the Mineral Advent Calendar

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

I dearly love this time of year, the sparkly lights, the cheerful music, the parties, the snuggly blankets, the cheesy movies – its FANTASTIC! And one of my favourite things is decorating the tree and our tree is a beauty!

Sparkly lights, lovely pine smell - the tree is the best!

Sparkly lights, lovely pine smell – the tree is the best!

Baubles are the glowing circular icing on the cake of the tree, and the best quality ones are made of glass. These baubles are often based on the original vintage baubles that were used throughout the last century. And glass is made from silica, the crystal form of which is Quartz!

Lovely vintage glass baubles from nordichouse.co.uk

Lovely vintage glass baubles from nordichouse.co.uk

 

A lovley quartz crystal photo from the MinDat website, taken by Rock Currier.

A lovely quartz crystal photo from the MinDat website, taken by Rock Currier.

 Quartz:

Chemical formula: SiO2
Colour: Colorless, Purple, Rose, Red, Black, Yellow, Brown, Green, Blue, Orange, and so on!
System: Trigonal
Hardness (Mohs): 7
Can you find it in the UK? Yes!

You can find quartz crystals all over the place, you can even find it easily yourself, especially on the beach!

Look for quartz crystals on the beach - but be aware that they will probably look rougher and white in colour than the lovely crystals you see in the shop!

Look for quartz crystals on the beach – but be aware that they will probably look rougher and white in colour than the lovely crystals you see in the shop!

For more information about Quartz please visit the MinDat website.