Monday, January 23, 2012

Quartz with Montmorillonite

Recently I came across some amazing new quartz specimens for my collection.  I will be using them to make pendants in the next few months.  Some of these items are extremely rare, so rare that many of the inclusions are still alluding me at this point.  I am going to show you a series of photos of my quartz with montmorillonite.  Try a search on google for quartz with montmorillonite and see how many images you can find.  It's not very many. 

Quartz with Montmorillonite and other minerals
These photos are of my quartz crystals with iridescent pink montmorillonite.  There are other minerals in these stones as well.  Perhaps mica is one of them.  The image I received from my supplier showed some very dirty, odd looking crystals.  I took a chance because I just had a hunch that underneath all of that mud, something spectacular was hiding, and I was right.

Quartz with Montmorillonite, mica and other minerals
These stones practically glow.  I have never seen anything like these before and it took quite a bit of research to figure out that the pink pearly mineral is most likely montmorillonite, which is a type of clay.  There is montmorillonite in bentonite clay. People have used montmorillonite for healing for centuries.

Quartz with Montmorillonite and other minerals
Quartz with Montmorillonite and other minerals
This one has a coarse pink powdery clay that has been falling out of the hole you see on top.  It is especially interesting because while inside the crystal it looks very opalescent, but the dust just looks like pink dirt on the outside.

Quartz with Montmorillonite and other minerals
I am so excited to work with these and hope they can handle the heat because these things are truly a spectacular find.  I think I'm going to use my new design to limit the amount of heat exposed to the stone.  The following is an example of how I am probably going to hang these.

Red Quartz Pendant
If there's one that stands out to you and you want a custom pendant, convo me through my etsy store at DoodlepunkArt.Etsy.com

Quartz with Montmorillonite and other minerals

Quartz with Montmorillonite and other minerals
Quartz with Montmorillonite and other minerals
Quartz with Montmorillonite and other minerals

Wikipedia has some good information about Montmorillonite:  

Great Close-up Image:  

One up for auction with blue:  

Spectacular:  

Quartz with Montmorillonite and other minerals
Quartz with Montmorillonite and other minerals

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Sunday, January 22, 2012

Real Unheated Citrine vs Heat-Treated Amethyst: How to Tell the Difference

Three Varieties of Citrine: Lemon Citrine, Naturally Heated Amethyst & Man-Heated Amethyst

Natural unheated lemon citrine wire-wrapped with copper wire and an antiqued copper chain.
Real Lemon Citrine Pendant from DoodlepunkArt

Updated & Clarified

This article was originally written at a time when the term “fake citrine” was commonly used in the metaphysical crystal community to describe heat-treated amethyst sold as citrine. Many people still search for phrases like “real citrine vs fake citrine,” reflecting widespread disagreement in the marketplace. In gemology, however, the distinction is not fake versus real, but rather between unheated natural citrine and heat-treated amethyst that appears yellow and is sold as citrine.

Gemologists consider heat-treated amethyst a legitimate form of citrine by color definition alone, even though its formation, crystal habit, and energetic qualities differ from those of unheated aluminum-lithium citrine, often called "lemon citrine." Both materials are yellow quartz, but they arrive at that color through very different geological and, in many cases, human processes.

This article has been updated to reflect that nuance while still teaching readers how to visually and structurally distinguish between the different types of “citrine” commonly sold on the market, including what collectors and metaphysical practitioners often mean when they refer to real citrine.

Wire-wrapped raw lemon citrine crystal with an olive-yellow smoky color.
Unheated Smoky Lemon Citrine

What Citrine Is (And Why the Term Is Confusing)

Citrine is a yellow variety of quartz crystal and has a Mohs hardness of 7. Also called lemon citrine and (sometimes lemon quartz), it is known in the metaphysical realm for its ability to promote prosperity and abundance. Energetically, it helps dissipate negativity and promotes optimism. Citrine aids in manifestation by inspiring confidence and motivation, and by aligning the user with his/her true will. Citrine is linked with the sun and acts on the solar plexus chakra.

Bright yellow lemon citrine sphere wrapped with copper wire into a wire woven ring
Unheated Lemon Citrine Sphere Ring

There are other yellow quartz varieties, including golden healer/ferruginous quartz, tangerine/iron-stained quartz and some amphibole quartz, all colored by inclusions, but these are not considered citrine.  For a gemologist, it does not matter what elements are causing the yellow color inside of citrine, as long as it is transparent color zones, not inclusions or coatings. However, for someone who is using citrine for metaphysical purposes, the color is not the only thing that matters.  We care about what elements cause that color, as they each have different healing properties. 

Raw smoky lemon citrine crystal wire-wrapped and hung on an adjustable antiqued copper chain.
Unheated Citrine Pendant from DoodlepunkArt

How Citrine Forms: Three Common Pathways

Many websites and books claim that iron is what colors both natural citrine and amethyst, while at the same time listing the healing properties for lemon citrine.  There are actually three different types of citrine:

  • Heat-treated Amethyst - Most citrine on the market is amethyst crystals that are heat-treated to product a yellow crystal.  They are colored predominantly by iron and have healing properties similar to amethyst.
  • Naturally Heated-Citrine - These are amethyst that have been exposed to natural heat.  This is a very rare occurrence.  Healing properties are similar to amethyst or heat-treated amethyst, but can have their own unique nuance.
  • Aluminum Citrine, or Lemon Citrine.  Color is not caused by iron and doesn't require heating for its yellow color.  Healing properties are very different from those of amethyst. This is the most highly sought after variety for those who use crystals for healing.  This is considered the true manifestation stone, activating the solar plexus chakra.  This is a rare stone. 

In quartz, trace elements such as aluminum or iron substitute for silicon within the crystal lattice. These substitutions create charge imbalances that are compensated by ions like lithium or hydrogen. When exposed to natural radiation, these impurity complexes form transparent color centers that produce amethyst, smoky quartz, or citrine coloration. Heating can alter or destroy some of these color centers, changing the crystal’s color without changing its chemical composition. In amethyst, this results in a yellow crystal.  In citrine or smoky quartz, the color simply fades.  I discovered that the hard way when soldering citrine crystals and the stones got too hot. The smoky color disappeared, and only a light yellow remained.    

Intense olive-green-yellow raw smoky citrine crystal from Ural Mountains in Russia
Smoky Citrine Specimen from DoodlepunkArt

Note that the elements that color smoky quartz and citrine are the same, it is just the ratio of these elements that determines whether the color zone is yellow, green, brown or black or a combination of these.  This is why both of citrine and smoky quartz can come out of the same mine.

One More Variety: Ametrine

Ametrine is a variety of amethyst where it is either partially heated, or part of it was re-irradiated.  I have seen contradicting opinions as to whether it ever occurs naturally, but I have read that it can be created by heating amethyst, then protecting part of the crystal with lead and re-irradiating it. I imagine the conditions for this to happen naturally would be quite rare.   

Champagne-colored lemon citrine sphere in a silver soldered setting hanging on an adjustable black satin cord
Champagne Colored Unheated Citrine Sphere Pendant

So How Can You Tell Which Type of Citrine You Have?

Since amethyst is found in abundance, 99% of citrine sold on the market is heat-treated amethyst.  Unfortunately, with all the heat-treated amethyst flooding the market, it can be challenging to find real unheated lemon citrine.  And there is a lot of misinformation out there making it even more difficult to know what to look for.  What makes it even worse is that most heating happens at the mine, therefor many sellers do not even realize it is heated.  Brazilian mining and export law does not require disclosure of treatments at the mine level, leading the seller to unknowingly pass along bad information.

And to add to the confusion, some books and resources will also list the healing properties of lemon citrine, and show the photos of heated citrine.  Others will accurately show each as having their own unique properties, but not really explain how to tell them apart.  If you are looking at citrine for its metaphysical properties, you will need to be able to identify whether it is lemon citrine, or heated-amethyst citrine, because they do not have the same healing properties.  Heated-amethyst "citrine" properties are actually more similar to amethyst.  

raw olive-green-yellow specimen of unheated lemon citrine mined in Sichuan, China
Unheated Smoky Lemon Citrine from Sichuan, China

Color Ranges and What They Can (and Can’t) Tell You

The most common property that people look at when trying to identify minerals is color, and while this is usually inadequate on it's own, there are some distinct differences in color between most lemon citrines and heated amethyst citrines. Now, there are always exceptions to these rules, but most crystals on the market will fit into these color zones.  

A spectrum showing warm colors on the right and cool colors on the left demonstrating how the color range of heat-treated amethyst usually range on the warm side of yellow, while lemon citrine ranges on the cool side
Cool Colors On the Left - Warm Colors On the Right

Imagine a rainbow/spectrum with a line going right down the center of the color yellow.  From this line, the colors on the right gradually get warmer, and to the left the colors gradually get cooler.  This illustrates the color ranges of most heated-amethyst and lemon citrine.  To the right of the line is heated-amethyst and to the left is lemon citrine.

a cluster of bright goldenrod yellow heated-amethyst citrine crystals
Classic Warm Hue of Heated Amethyst Citrine

Now I realize that this doesn't realistically represent the exact colors of the crystals, but I hope it illustrates my point.  Most heated amethyst citrine is warmer in color than lemon citrine.  Even if the color is yellow, most lemon citrine ranges cooler in color than heated amethyst, and although heated-amethyst can also be yellow, most is orange, red, champagne, amber or brown.  This alone will help you differentiate a good percentage of specimens on the market.

silver soldered pendant featuring an olive-green-yellow smoky citrine crystal with long, straight m-faces
Unheated Smoky Citrine Crystal Pendant

Notice how all of the lemon citrine specimens I have posted range a bit cooler on the spectrum, even the ones that aren't smoky at the top of this article?  Also, if it is a smoky olive-yellow, I am quite sure it is not possible to be heated-amethyst, as heating destroys smoky color.

Now there are exceptions to this.  There are many crystals that are champagne colored, or sit right in the middle of yellow, and it can be quite hard to distinguish whether they are heated-amethyst or lemon citrine.  There are also some very rare unheated citrines with an intense warm yellow hue.  It can be very tricky to know if these are the very rare naturally heated variety or lemon citrine.  These situations require you to utilize other characteristics, such as crystal habit and dichroism (introduced at the end of the article.)     

A cluster of purple amethyst crystals on a matrix from Brazil
Untreated Amethyst Cluster From Brazil

Crystal Shape and Growth Habit (One of the Most Reliable Clues)

Very simply put, crystal habit is the shape the crystal grows in.  Most amethyst on the market have a very distinct shape.  Now, this shape won't be present in 100% of heated-citrine crystals, but it has a high probability of helping you differentiate most heated-amethyst from lemon citrine.  

A cluster of heated amethyst citrine crystals on a matrix
Heat-Treated Amethyst Cluster From Brazil

Dog-Toothed Crystals

Brazil is by far the largest supplier in the world of both amethyst, and heated-amethyst citrine.  Fortunately, this citrine is very easy to identify by shape. The majority of the amethyst produced grows in geodes or clusters.  Those are then broken up and sold as either small clusters or single crystals.  

A single orange crystal of heat-treated amethyst citrine showing the common "dog-tooth" shape
Heated Amethyst from http://www.the-vug.com/vug/vugfakes.html
Notice the orange color and Dog-Tooth shape? 

Because the crystals grow so tightly packed together, the hexagonal sides (called m-faces) that would normally run roughly parallel along the crystal toward the termination (point) are often distorted beyond recognition.  The neighboring crystals cause severe growth interference of the crystal habit, resulting in a jagged diamond shaped crystal, called a "dog-toothed" crystal. If a raw crystal has this shape, it is safe to conclude that it is heated amethyst citrine.  

A pile of purple Brazilian amethyst crystals sitting on a placemat demonstrating the classic dog-toothed shape and white base with darker colored points
Dog-Tooth Shaped Amethyst Crystals

Lemon citrine can grow in clusters, but typically they still have m-faces, similar to smoky quartz.  If it has hexagonal sides, that either run parallel or taper toward the termination, you can rule out most Brazilian heated-amethyst citrine.

a hand holding a beautiful deep greenish yellow smoky lemon citrine specimen - the crystal has long straight parallel m-faces and a smoky phantom near the termination
Lemon Citrine With Smoky Phantom - Long Parallel M-Faces

If the citrine crystal gets fatter as it get's closer to the termination, most likely it is heated-amethyst citrine from a geode.

a selection of heated amethyst citrine crystals next to a coin to show the size - the crystals have dog-tooth shape, orange color and are lighter at the base and darker at the tip
Brazilian Heated Citrine - No M-Faces, Widest At Termination

Distribution of Color Within the Crystal

Another characteristic common in amethyst and heated-citrines from clusters is the tendency to be white at the base and dark at the termination.  Periodically natural lemon citrines do have this color zoning, but nearly all heated-citrine from geode have this trait.

a single crystal specimen of heat-treated amethyst citrine with orange color, dog-tooth shape and white base
Dog-Toothed Heated Citrine with White Base & Orange Termination

Unheated citrine is commonly more even colored throughout the crystal, or it could be darker at either the termination or the base, or it can have phantoms. But the majority of amethyst from geodes are dark at the termination and light at the base.  This trait alone can't identify which crystal you have, but used in combination with the other characteristics you can identify most heated-amethyst citrine.  

Smoky lemon citrine with straight m-faces from Sichuan, China
Smoky Lemon Citrine With Straight M-faces - Sichuan, China

Dichroism: The Coolest Citrine Crystal Test

If you’ve gotten to this point and still can’t tell whether your specimen is lemon citrine or heat-treated amethyst, don’t worry. Some stones fall right on the middle of the yellow spectrum, are champagne-colored, or are cut so you cannot see the crystal habit and color zoning.

One additional trait that can help is dichroism, a subtle color shift visible when a crystal is viewed from different directions. While quartz is not strongly dichroic overall, some natural lemon and smoky citrines can show a weak directional color change, often shifting between yellow and greenish-yellow or smoky tones as the crystal is rotated in the light.

a pile of unheated lemon citrine crystal balls, some are pale, some yellow, some smoky
Various Lemon Citrines, Some Smoky, Some Pale

Amethyst, including heat-treated amethyst sold as citrine, does not display true dichroism. Its color appears uniform regardless of viewing direction. For this reason, a noticeable directional color shift can be a useful supporting clue for identifying unheated citrine, especially when combined with crystal habit and color distribution.

A tumbled piece of heat-treated amethyst citrine showing bright goldenrod yellow-orange color
My First Ever Citrine (Heat-Treated Amethyst)

A simple way to check for dichroism is to view the crystal against a white LCD screen and slowly rotate it. Often natural lemon and smoky citrines will show a subtle directional color shift, while amethyst and heat-treated amethyst remain uniform from all angles.

I will be filming a video on how to do a dichroism test soon, so check back for that, plus for a few more tidbits I ran out of time to complete.  I removed all of my links to lemon citrines for sale by various vendors because they were from 14 years ago - this rewrite was long overdue.  Hopefully it is a lot easier to get through and the new knowledge I have gained will help you find your perfect lemon citrine crystal.  If you are still having issues, you can contact me on Etsy, and I would be happy to help you find one.  Also, please visit me on YouTube at https://www.youtube.com/@doodlepunkart where I am teaching rockhounding, geology, crystallography, lapidary and wire-wrapping.

A purple amethyst crystal cluster on a green matrix, the crystals are white at the base and purple at the tips
Amethyst Cluster

Thanks so much for reading.

If you liked this, you might also enjoy:

Red Phantom Quartz and the Important Work of Grounding

Carnelian Metaphysical Properties and Gemstone Information

Black Tourmaline (Schorl) Metaphysical Properties and Gemstone Information


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Three dog-tooth shaped amethyst crystals
Dog Toothed Amethysts

One of my favorite quartz websites has a page on citrine that explains the science behind its formation in greater detail:   http://www.quartzpage.de/citrine.html

one purple amethyst crystal specimen with a dog-tooth shape
Dog Toothed Brazilian Amethyst
A golden-yellow heated amethyst citrine crystal with a diamond-like shape
Dog Toothed Heated Citrine - White Base