Tuesday, 22 January 2013

What's In A Name?

After reading my blog on amethyst, in regard to "green amethyst" being a misnomer, I was asked "I've heard of a green sapphire, is that wrong too?". There's no straight answer to that. The term is certainly widely used and accepted, but the naming of gemstones is complicated.

Sapphire, by definition, is normally a blue stone, in fact that's what it's name means. It's the blue form of corundum, which like many gemstones, can certainly come in other colours, but when it does, we sometimes give them other specific names. If corundums are pinkish red we call them rubies, for example. Certainly, corundum can come in green, and other colours too, it all depends on impurities. Therefore a green sapphire is a rather confusing term to use but it's all we have (for now) and it's just one example of why arguments about names of gemstones are common, and can sometimes get a bit silly.

Many minerals, including corundum, beryl, quartz, and others, when pure, are actually colourless, but impurities such as iron, chromium, copper, and so on, cause coloured varieties. Colours can also be changed artifically in some minerals by heat, irradiation, or even dye. So if you use colour as a guide for the name, it could, theoretically, change name if it changed colour. Hmm.

It gets even more complicated on an international basis. When people think of jade, they usually think of a green stone. In fact a common name for jade in some countries is..."greenstone". But jade can come in many different colours. Then there's the issue of what precisely jade is - several different minerals are known as jade quite legitimately, and quite a few more simply "in the trade". In fact a definition of jade, if you want to be accurate, would necessarily take several paragraphs of explanation.

It's no wonder then that potentional buyers almost need a course in gemology. Then, popular names change with "trends" anyway, so you still have to keep up.

A popular gemstone recently is "mystic topaz". To be harsh, this is fake coloration. However, the process used is really not any more extreme than other common and accepted processes in the industry. Clear topaz is coated with a layer of titanium. You may be familiar with the rainbow effects from titanium, well, this is the rainbow being seen through a faceted clear stone. The effect is really quite something. When a customer in a jeweller's store asks if the stone is genuine, he will be told yes. It is, after all, real topaz. And a titanium coating is no different to the rhodium coating applied to many high end rings.

If instead he were to ask "is it pure?" he might get closer to the truth, but what is "pure"? As noted above, the colour of a gemstone is created by impurities.

A better question, if it matters to you, is to ask if the coloration is natural. There is a better chance of a straight answer then, but no guarantees. Salesmen can have creative ideas about what "natural" means too.

So why does a treated topaz get a fancy name like "mystic" while a naturally occuring gemstone like green sapphire gets nothing? In a word: marketing. Back when sapphires and rubies were first found, nobody knew they were the same mineral. At that point in time, if a green sapphire had been found, it would almost certainly have been called an emerald. And why not? Even today the word  for emerald in some languages is the same word as that meaning "gemstone". At least when we say emerald, we are expecting green.

Confused yet?

Friday, 18 January 2013

Size Matters!

A collection of a few things that have cropped up regarding size over the last year or so, in discussions with all sorts of people on the topic of jewellery.

1. "Why are beads etc, always described in millimetres?" 

Well, quite simply because most of the world, notably the places where beads and findings are made, and most people who make jewellery, use the metric system. Even those who don't use metric in other aspects of their life are accustomed to buying beads in metric sizes, and it just becomes second nature, much as an electrician uses wire gauges when he's talking about his work.

Once you get used to the metric system, it's much easier, which is why it's so popular. The problem is, when you are not used to it, in visualizing the size of something when it is described. Considering just how important the metric system is in the modern world, I recommend obtaining a ruler marked in centimetres and millimetres for ALL shopping online. This is a much easier guide to have around than any amount of conversion charts. This is the future!

2. "How do I measure for a bracelet?"

Not as simple as it sounds, I've seen a few errors happen. Your wrist measurement is not the size you need. And it's no good adding on "a bit" for luck, as it were. What you should do is measure another bracelet that fits nicely. First, measure it open, laid out straight, and include the clasp. Then measure the inside of it when done up. Give these two measurements to your bespoke bracelet maker. Half an inch makes a HUGE difference with a bracelet, so it's important to measure accurately. If you don't have a tape measure to bend around the inside, use a piece of string, and then measure that on a straight ruler.

3. "It looked a different size in the photo."

When jewellery is photographed it is done so to capture its beauty. This may involve a whole necklace being seen in a small image, or a ring being blown up to several times actual size. Most people understand that much. Nevertheless I've had customers complain that an earring was much smaller than expected (I always list the size, but that's a separate matter). Now, this is despite the earwire being in the photo. Look at the screen. Hold your thumb up to it. The length of an earwire, in reality, is roughly the length of your thumbnail (or maybe a tad smaller if you have tiny hands). This will give you an idea of scale, regardless of the size of the image itself, or how it is displayed. If the earwire is TWICE the length of your thumbnail on-screen, then the rest of the earring is half the size of that displayed, in reality, also.

4. "Why is a bracelet only slightly less expensive than a necklace? Surely it should be half the price? It's only half the materials".

This might be fair if you were talking about a commercially-made gold chain. But with hand-made jewellery the materials are not the bulk of the price, the maker's time is. Depending on the design, the time it takes to make a bracelet may be as much as 2/3 the time to make a necklace. Then, when you do add on the materials, this can take it up to around 3/4.

If you have any questions, on this or any other topic, feel free to ask!

Friday, 11 January 2013


Amethyst is, by definition, the purple variety of quartz. For this reason there is no such thing as green amethyst, and the stone thus labelled is simply green quartz. Colours range from almost pink to a rich deep purple. Quite often the colour is artifically enhanced by irradiation, which is virtually impossible to detect. As the end result is pleasing, most people have no objection to this, the question simply remains as to value. World supplies are plentiful, and even if all the naturally coloured ran out, there is an almost endless supply of quartz that can be irradiated.

Therefore even the highest quality amethyst is a good, economical alternative to more expensive precious gemstones and is increasingly popular in mainstream jewelry, despite generally being outrageously over-priced. Interesting to note is that the banded (striped) stone, which was often seen as poorer quality in previous decades, is now enjoying favour much as it did in Roman times.

Another quartz, the yellow citrine, is generally heat-treated amethyst. Natural citrine is extremely rare and extremely expensive, not often found on the normal market. A related stone, ametrine, a dual coloured combination of amethyst and citrine, also occurs naturally, but in very limited quantities, and irradiated quartz is again the most widely available stone. Customers should not be afraid of artificially enhanced gemstones, but should consider value accordingly. As the mark-up on all gemstones is high, it might be fair to take into account the expense incurred in these enhancing processes. In any case, a stone is worth whatever the customer is willing to pay for it.

Amethyst and its close cousins are relatively easy to shape, and therefore many different beads and pendants are sold, in addition to the cut stones. Natural crystals are also available in considerable size, and there are whole caves to visit if you are a dedicated fan.