Gemstones as Minerals

I am fascinated by minerals.  We so often see gemstones in a final form as faceted stones or polished beads that it can be easy to forget what these substances look like in their native state.  The Lyman Museum in Hilo, Hawaii has a small but excellent collection of minerals.  Each specimen is notable either for size, rarity, or beauty.  Here are a few that particularly caught my eye ...

I spotted a huge, beautiful brown zircon, cubic, almost two inches on a side.  Never seen one that shade or that size.  There was a pyrite sample with the characteristic cubic box shape.  This one had several "boxes" stuck together at the corners, the largest appeared to be about 2.5 inches on a side.  The pattern isn't unusual for pyrite, but this one was smooth and perfect.  The surface of the crystals was shiny and almost mirror-like.

Some of the minerals had colors that surprised me.  There was a flourite sample with colors ranging from orange and burgundy to teal and lime.  A stunning chrysocolla from Arizona was a vibrant, glowing, light blue green.  An azurite sample was a deep, dark midnight blue, and sparkled like stars from reflections off of the facets of hundreds of tiny crystals.  Even the rose quartz was notable.  It was a perfectly uniform gorgeous pink, studded over with crystals.

The collection contained a sample of carved minerals.  This included ones I'd seen before, such as jade, carnelian, and malachite.  But there were other carved items from minerals I haven't seen used this way very often, such as lapis lazuli carved into a statue of a horse, and a head carved from aquamarine.

The petrified wood samples were excellent.  There were not simply small chunks, but full circular cross sections from trees, with rings preserved now as stone.  The process of turning something like a tree into a stone is amazing, and in this case left behind small crystal filled geodes right in the "wood."

Such a wonderful visit is always inspiring.  The next time I pick up a smooth bead of azurite, I will remember the spectacular mineral of midnight blue, with stars flashing. 

Peridot - Part Four: The Universe Makes Stained Glass Windows

Some of the most beautiful meteorites in the world (and out of the world) belong to the pallasite class of meteorites.  Many pallasites can be recognized immediately by their characteristic crystals of greenish olivine embedded in an iron/nickel matrix.  When these meteorites are cut into thin slices, light can shine through the translucent olivine, creating stunning lattices of metal and gemstone.

The example at left is the meteorite Esquel.  Gorgeous gem quality olvine, known as peridot of course, is liberally strewn through a shiny metal frame.  It seems so perfect, one might think it was manufactured.  But these incredible rocks formed naturally, far away from Earth.

The meteorite Imalac is also a pallasite, with a higher density of olivine to metal, although the olivine is of a more golden hue, and seems less gem-quality.  Some pallasites are almost all metal, while others are predominently olivine.  Each is unique, its own version of a glittering mineral 'window.'  It once was thought that pallasites must come from the interior of an asteroid-like body - the place where the olivine mantle met the iron/nickel core.  But recent studies have indicated that things are not so straightforward.  Pallasites are a glorious mystery.

This gemstone gives us an immediate connection to the heavens.  Something as simply beautiful as peridot is found in abundance in the mantle of the Earth, and is one of the most basic minerals in space rocks, too.  Of course, the Earth is really just a big space rock, itself.

Image Credits: Slice of Esquel meteorite, from flikr via Creative Commons, CC 2.0, Bistrosavage. Closeup of Imilac meteorite, original image from flikr via Creative Commons, CC 2.0, aakova.

Crystal in Handmade Jewlery - Part Four: The Shape of Things

Structure and composition aren't the only characteristics that help define the word "crystal" in common use.  For some people, the internal order and composition are not important, and what they mean when they say "crystal" is "has a regular geometric shape ending in a point."  In other words, the shape of the stone is the key factor.

This is a meaning often encountered in sites that deal with gemstones and their symbolic properties, such as healing.  This meaning might also be encountered on sites interested in selling materials for use in wicca, like wands for altars or pendulums for divination.  As noted in previous posts, this use of the word "crystal" is not incorrect - it is a reflection of history and culture.  There are many people who would be disappointed to purchase a "crystal" and find it isn't "crystal shaped."

Crystal points do make lovely jewelry, either drilled through as beads or wire wrapped as pendants.  The shape evokes a sense of mystery and magic.  Depending on the nature of the stone, they might range from delicate to sharp, and so might need to be treated with some care.  No two points are ever exactly the same unless they are mechanically cut or lab grown - gemstones all have natural variation.  Because of this pairing them for earrings or to use in sets takes some patience and design skill.

So to wrap up this four part series on crystal, the "point" again is know what you are using in your designs, and purchasing from your favorite sites.  One simple word like "crystal" does not mean the same thing to everyone, and so be sure to get specific details before you buy.  That way you can be certain you will love your jewelry when it arrives, and treasure it for years to come.

Image Credit: Quartz Crystal, Rob Lavinsky, CC 3.0, Wikimedia.org

Crystal in Handmade Jewelry - Part Three: Crystal Versus Glass - Composition

All Swarovski crystal (in
other words, lead glass)
and sterling silver suncatcher

Having taken a look at Crystal Versus Glass - Structure in my most recent post in the series, let's talk here about chemical composition.

First things first - how is it that a 'wine glass' can be 'crystal'?  Didn't I say previously that crystal had an ordered structure and glass did not?  Yes.  Crystal wine glasses aren't crystal.  They are made of glass.  They are made of a specific kind of glass that has had lead added to it to make it more reflective and prismatic.  The use of 'crystal' to describe this substance is historic, coming from Murano glass manufacturing in Venice.  In those days the manufacturers were trying to imitate some of the properties of natural quartz crystal.  This idiom, or convention, has remained.  'Lead glass' is the same as 'lead crystal' is the same as 'the stuff my crystal wine glass is made of.'

This confusion of terms has translated to the bead market, where both glass, lead glass, and synthetic and natural crystal are all used side by side.

So what is it about high quality, expensive 'crystal', like say Waterford, that makes it so desirable?  Regular water glasses, even if nicely etched and cut, do not have the flash and brilliance of, say, Waterford crystal faceted wine glasses.  As I said before, lead has been added to regular 'glass' to make it 'lead crystal'.  Lead increases the index of refraction of regular glass, which means that light going through the material is reflected around more, and also split like a prism.  'Fine cut lead crystal' is a phrase that means a sparkling, fiery wine glass that will look impressive on the dinner table.

Gorgeous trio of designer glass
earrings.  Even the Swarovski crystal
accents are of course glass.

The same is true for beads.  Beads made of standard glass will not have the same flash and brilliance as lead crystal, even if they are the exact same color and cut in the same way.  This does not mean that 'glass' is bad.  Not at all.  Remember, these kinds of 'crystal' beads are in fact glass.  This is simply glass with lead added to it make it sparkly.  Glass is a fantastic substance that makes highly desirable and sought after jewelry.  I adore glass, and am a huge fan of Murano beads, designer lampwork, and glittering dichroic creations.  The point is to know what you are using in your work as a designer, and what you are buying as a consumer.

I'll talk more about why I choose to use various glass and crystal materials in a later post!

Images:  Suncatcher and earrings are our designs, and available in our Etsy store.  Stop by to see these and similar items!

Crystal In Handmade Jewelry - Part Two: Crystal versus Glass Structure

Our 11" Suncatcher Talisman showing
off a variety of crystalline solids, such
as a smoky quartz faceted crystal
teardrop.

In Part One of my series of posts on 'crystal' I talked about many of the different definitions and uses for this common word in handmade jewelry business.  As this series continues, I am going to focus on each of the various views of 'crystal' and hopefully dispel some of the ambiguity.

A common place to find confusion is in the use of 'crystal' versus 'glass' in the materials listed for a handmade piece.  To a geologist, these terms have a specific difference based on structure.  To a bead artist, these terms are more likely to be differentiated based on chemical content.  Let's talk about structure first ...

'Glass' is a solid substance where the structure of the atoms is irregular and amorphous (and which will turn into a liquid when enough heat is applied).  There is no large scale order to be found in 'glass'.  Conversely, the structure of a 'crystalline' solid is very regular.  The internal matrix of a crystal is repetitive and highly ordered.

It is possible to have a 'glassy' form of a material that has the exact chemical composition as a 'crystalline' form.  The most most well known crystal is quartz, made of silicon and oxygen, SiO2, in a nice repeating pattern.  But SiO2 is also the major constituent of 90% of the glass in our everyday lives.  A crystalline substance can be formed by cooling a liquid slowly, allowing the atoms to line up into a nice, repeating pattern as the stuff becomes solid.  A glassy substance can be formed by cooling a liquid very quickly.  The stuff becomes a solid before the atoms have time to line up.

This means that any 'crystal' in a necklace need only be made of a solid with a repeating structure to be referred to as 'crystal'.  A designer that uses quartz crystal in a necklace will call it crystal, and be absolutely correct.  Yet this can be misleading if you imagine all crystal means 'Swarovski.'

I'll post soon about crystal versus glass - composition!

Jennifer

Crystal in Handmade Jewelry - Part One: More Than One Definition

Quartz crystal point in back, propping
up a rhyolite gemstone flecked with
crystal inclusions

Hello Gemstone Fans:

'Crystal' is a common constituent of handmade jewelry, but the word is very often used in ways that are confusing.  Is the designer talking about the composition of the material, its shape, its clarity, or saying it is a single piece of rock, uncut?  When designers describe their jewelry, sometimes they do not provide enough information to let the buyer know exactly what they are getting.  Unscrupulous sellers may even allow misinterpretations to remain unaddressed, hoping the buyer will think they are getting something of higher quality than what is actually included in the piece.

So to start, I simply want to point out how problematic the word 'crystal' can be.  In the first image above, we see a nicely formed quartz crystal.  Some people would call it a crystal because of the regular geometric shape.  Others might think 'crystal' because it is made of solid quartz.   A geologist might call it a crystal because it is a uncut chunk of a mineral in its natural form, or because its atoms are in a nicely regular matrix, instead of scattered about amorphously.  A geologist would also use the word 'crystals' to describe the granules of different minerals found in the rhyolite.

Crystal martini glass displays a pair
of earrings, each with a crystal
bicone bead on top.

More examples of 'crystal' are in the second image.  For some, the only crystal they are familiar with on a daily basis are cut crystal glasses and bowls used for dining or serving.  For others, the word crystal always means bright, sparkly, glassy looking beads, like those found atop the shells in this pair of earrings.  It may be that the chemical content of the beads isn't at all what they are thinking of, simply their common shapes, colors, and flash.

So with all the different ideas for what a 'crystal' is, or what 'crystal' can mean, there is no surprise that confusion exists.  Stay tuned here for more information about how you can be more informed about what is in your jewelry, and how to make sure you are getting exactly what you want!

Jennifer