Everyone knows the quartz variety called citrine, but did you know most of the “citrine” you find for sale isn’t natural at all? Yep, there’s a good chance you may actually just have some super heated amethyst or smoky quartz that’s been treated to resemble citrine.
Natural citrine can be just as you may find commercial citrine: pale yellow to darker shades of brown, but natural citrine is very rare.
A few days ago, I posted about proper handle, care, and organisation of minerals (and fossils). I wrote about how there are times you may receive a specimen with no identification, and I’ve had another one of those times!
Here’s one of my latest additions a friend picked up for me that came with no information card, so I thought it could be fun to post and see what you guys may think is there! You can’t always 100% identify just by sight - which is why you then do physical tests - but I’d love to see the results you all come up with just from looking at the images. I will reveal what’s in the photos at a later date to give enough time for people to do some detective work.
Beautiful Celestite/Celestine specimens by Scorpions and Centaurs on Flickr.
Chalcedony on Chrysocolla from irocks.
Here’s another example with one of my favourite combinations. I haven’t been on Tumblr lately, so here’s a photoset showing that awesome mineral habit called botryoidal. I’ll have new posts coming soon!
Hello! It’s not a silly question at all. Minerals come in all different shapes, sizes, and numbers on the Mohs scale of hardness. Aragonite comes in at 3.5 - 4 (1 being the softest, 10 being the hardest [i.e. diamond]). I have many different forms of aragonite: ones like in my experiment, and ones like this.
When it comes to uses, I guess it all depends on what you want to do with it. Mine are a mixture of decoration, jewellery, or doing experiments. Aragonite does have a use in aquariums to help replicate natural ocean life, and help balance levels (like pH) in tanks. It develops in mollusk shells and corals too (plus in the ocean and caves), and you’ll also see many ammonite fossils showing signs of aragonite, for example.
My one aragonite specimen is pretty durable, but I always handle every specimen of mine with care no matter the Mohs hardness. As with what happened with my Project Aragonite experiment a few days ago, someone moved my glass container and all the aragonite fell off in an instant right into the vinegar. But of course it grew back within a day to even more than I originally had. Right now it is currently drying out and hardening, which will be sturdy enough to handle and move around soon enough. An aragonite specimen like one of mine with the pseudohexagonal twinning structures is a bit stronger than some fibrous aragonite. Those have a greater chance of breaking due to the way they form.
It’s a very fun experiment! It’s simple and there’s not much you need to do other than pour white distilled vinegar into a glass container with the popcorn rock and watch them grow. You’re welcome, and thanks for the ask!
Project Aragonite: Day 16… or 1?
So yesterday after my Day 15 post, someone moved my glass jar and all the aragonite crystals fell right off. I wasn’t upset at all about it, but I made sure now only I handle the container. The past two weeks, the jar has been in controlled temperature and light to show the slower process of growth at work. This time, seeing as they all fell off, I decided to show you guys what high heat and light can really do to this rock.
The above photos you see were taken within the last hour, and all these crystals grew on the rock within less than 24 hours. Why? Again, high heat and light! Aragonite loves those conditions, and so you get a super fast experiment. Usually, it can take 1-3 weeks to have crystals grow; all depending on the conditions around the jar. Within less than a day, I grew more aragonite within that period of time than I did in two weeks. I should have set up a camera to do a time lapse, but that can be done if I find the time.
Pretty cool how quickly they can grow, right? So a reminder, if you want a slower process of crystal growing, control lower temperatures and timed lighting (which is what I originally did) will be needed. If you want quick growing, higher temperatures and more light is needed for that process to be sped up.
Project Aragonite: Day 15.
Well, we have a little more activity with the growth of aragonite. Finally, some crystals have grown on the rock itself, plus much more along the walls of the glass jar. I’ve barely been on Tumblr, which is why I wasn’t able to update this project until now. The vinegar has evaporated enough to expose the top half of the rock, so more crystals should continue to grow! I have the rock in direct sunlight to help the process of growing the crystals more successful as well. As the vinegar continues to evaporate, more and more crystals will grow. Here’s an awesome example of someone’s popcorn rock after all the vinegar evaporated on YouTube.
Watermelon tourmaline is so awesome. I have a few on display, and they always look like candy whenever I pass them!
Photo via Wikipedia
Project Aragonite: Day 7.
So week one has passed and there hasn’t been too much to update you guys with. The vinegar has just begun to expose the limestone, so with some time crystals will be more visable. More of the mineral has formed along the inner walls of the square glass jar, which is always a good sign! For this next week, I’m moving it into warmer temperatures with more light to help the crystals grow faster now that the tip of the rock is exposed.
These are some photos of the aragonite on the inner walls for you guys to see. I’ll try to update more (daily) as the process continues, but the last 5 days have just been uneventful, so I didn’t see much of the point.
Did you guys know rubies and sapphires - which are usually seen in jewellery - are actually the same thing?
When I say the ‘same thing’, I mean they are both varieties of the mineral corundum, which forms mainly in metamorphic rocks, but not limited to. They have the same chemical formula, Al2O3, yet come in different colours and are known to the general public as different ‘stones’.
Rubies and sapphires both must have a certain amount of colourisation and hues to be considered a specific kind of that gemstone. Sapphires can also come in other colours than the dark blue most people know.
The reasons for all these different colours and hues is dependant on the amount of elements found within the mineral.
For example, the ruby’s pink-to-red colours are because of the presence of the element chromium.
Sapphires come in a more array of colours - blue, purple, green, yellow, pink, etc - due to different elements being present like copper, iron, and magnesium; just to name a few.
The best part is, these are all impurities. Funny how impurities actually make something even more beautiful, right? As well, we all know the diamond is the hardest gemstone, coming in with a 10.0 on the Mohs scale, but rubies and sapphires come very close with a 9.0.
Oh yeah, and these varieties can be fluorescent too. Just a bonus to add to the pure awesome that is corundum. Next time you see these gemstones set in jewellery, you’ll now know some new facts to tell others!
Photo credit goes to:
- Sapphire ring: gemteck1 on Flickr
- Ruby ring: paparutzi on Flickr
- Corundum (var. sapphire): Orbital Joe on Flickr
- Corundum (var. ruby): Orbital Joe on Flickr
Stibnite is an awesome mineral, but also one that can be potentially toxic, so it must be handled with care (and always wash your hands!). It’s an antimony sulphide, Sb2S3, and also a soft mineral that comes in with only a 2.0 on the Mohs hardness scale. The specimen above is called “Spectacular Stibnite”, and the largest specimen ever displayed, and very rare due to its size/crystal structures. It’s also 1,000 pounds and originally from a Chinese mine.
This brilliant mineral was created around 130 millions years ago when antimony and sulphur were dissolved in water heated by volcanic activity, and then deposited between layers of limestone. For those beautiful crystals to grow so large, it would have been deposited in a pocket at one point, which is very lucky it was found and not destroyed while workers were in the mine.
It is on display at the American Museum of Natural History, New York, NY.
Photo credit: Ryan Somma on Flickr
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