Buying semi-precious beads – a guide to size and shape

If you’re new to working with semi-precious gemstone beads and you want to start buying them you should bear in mind a couple of things regarding their size and shape.

Does size matter?

Common sizes for round beads.

Gemstone beads are measured in millimetres. Round beads are measured by their diameter (the widest part of the bead), so you will often see items listed as 4mm or 10mm. Easy enough, right?

It gets more complicated because it’s common to expect a tolerance of up to half a millimetre plus or minus on your beads. It means those 4mm beads could actually be 3.5mm. Anyone familiar with buying semi-precious beads will no doubt have encountered this.

Cutting and shaping stones is notoriously difficult – some stones are softer than others and therefore easier to shape while others are much harder to cut, so the finished product does vary. But do you need to worry about this?

Most beaders are aware of the tolerance and can work around it. But you might get stuck when you try to string a small 4mm round with a large 4mm and discover an entire millimetre difference. So if size is critical to your design you should check with your supplier first.

Temporarily strung or loose beads?

You will often see beads for sale individually, in packs or on strings. What’s the difference?

Typically semi-precious beads are cut, polished and then put on a temporary string by the factory before being sold on. The standard length of these strands ranges from 38 – 40 cm.

Some retailers will break these strands up and sell the beads individually, while others (like BeadShopUK) will sell them by strand.  

Generally speaking, it’s cheaper to buy your items on a temporary string rather than individually. It’s the same principle of buying bulk that you encounter whenever you go to the supermarket.

You can calculate how many beads you can expect based on the diameter of the bead and the length of the strand. For example, a 40cm strand of 10mm beads will have 40 beads (just divide the strand length by the diameter of the beads)

However, because beads do vary in size, and the strand length can vary, you should use this calculation as an estimate. If you need an exact number of beads for your deign it’s best once again to check with your supplier.

Tip:  To quickly measure the size of your beads, count ten beads and hold them against a ruler - 10 x 4mm = 4cm, 10 x 6mm = 6cm etc.

10 x 8mm Carnelian Beads

Shapes or rounds?

There are all kinds of shapes on the market. Do you want round beads as spacers, or maybe some cubes, rectangles or ovals?

A variety of semi-precious stones and shapes.

Shaped beads are becoming increasingly popular with jewellery designers and the availability of shaped gemstone beads is increasing. Shapes can add individuality to a design but you should bear in mind that you will have to use spacer beads so that the shaped bead hangs properly.

That’s where the fun comes in – will you use small round spacers of the same type of stone? Or are you going to find a contrasting colour from another variety? The designs are endless!

At the end of the day it’s all about experimentation, so find the size and shape that works for you and have fun trying out your designs.

Hopefully this brief article will give you an overview of what you can expect when buying semi-precious gemstone beads, but if you have any questions or comments, please feel free to get in contact.

Grading Gemstone and Semi-Precious Beads. What does it all mean?

If you’ve ever bought semi-precious or gemstone beads you might have noticed that there are all kinds of grading systems in use. One shop might grade from A-D and sell Amethyst beads as A grade, another might grade from AAA-B and sell them as AAA or even A+. So, which is the best? 

At BeadShopUK we often get asked about grading gemstones, so hopefully this article will clarify a few things.

A Grade Amethyst beads?

The first point to bear in mind is this: when it comes to semi-precious stones there is no standard, internationally recognised system for grading as there are for precious stones such as diamonds, which are graded according to cut, colour, clarity and carat.

Effectively it’s up to the factories and retailers to grade their own products, and they all use different grading systems. If you’ve ever been confused by this then you’re certainly not alone!

The second point to remember is that one shop’s A Grade Amethyst might be described as B or even C grade by another shop. Same quality, different grading system.

The sad fact is that people want to sell you their items and it sounds great if the stone is A Grade, or even better AAA grade. So, try to find a reputable supplier with whom you can build a relationship and who will answer your questions on what grading system they use.


Grading starts with the rough material.  The highest grades are usually reserved for cutting individual faceted stones and it is the C and D grade material (sometimes referred to as “bead” grade) which is used for cabochons and beads.  Sometimes you will see beads which are classed as “facet grade” – these would be of the highest quality and the price would reflect this!  Most of the other beads on the market would be cut from the C and D grade material.

Finally, the key to understanding grading is to ask lots questions, read up about how gemstones are formed and how they are manufactured because it’s up to you to decide what’s the best quality for your needs.

B Grade Amethyst beads?

Anyway, you shouldn’t be put off by a lesser grade. Some stones may have inclusions in them, meaning they don’t grade highly, but those inclusions are what give the beads their colour and texture and can look absolutely stunning in a piece of jewellery. The key is to find what works for you.

As a supplier of semi-precious beads, we at BeadShopUK.com know it can be a minefield when describing stones. After all, one man’s A grade is another’s B grade. So we don’t subscribe to a formal system of grading.

Faceted Amethyst Gem

Instead we aim to sell only very good quality beads and let the customer know exactly what they are buying by taking clear photographs.

When we do have the same stones of different quality we mark the better ones A Grade and the lesser quality as B Grade.

In some instances when we have received some very bad quality stones we won’t bother selling them online at all because we don't want to disappoint our customers we only want to ship excellent quality items. Instead we sell them in our pound box when we go to a bead fair.

You can go to our website and see how we sell our Amethyst Beads.

Common treatments for colouring gemstone beads. Should you be worried?

These days it’s common for natural gemstone beads to be colour enhanced. This is nothing new. In fact the practice goes back thousands of years. But is this something you should be worried about? Should you avoid enhanced beads or embrace them?

To answer this question you should first be aware of how stones are colour enhanced.

Perhaps the two most common ways are by dying and by heat treatment, and many gemstone beads on the market will have been treated in these ways.

Natural colour Carnelian

Stones, such as agate, are soaked in a dye that enters through the porous structure and leaves a colour change. Sometimes the dye can’t enter the more dense structure which leaves intermittent bands of dye and natural colour. This is most clearly seen in various dyed agates.

Dyed agates are actually quite easy to detect as the colours used are unnaturally bright. 

So, should you care if your stones have been dyed?

Firstly you should take care when purchasing dyed beads as the colour can sometimes run. And nothing ruins your day faster than a customer complaining that her favourite blouse has been ruined by the beads she bought off you!

Also beware that some dyes are not permanent and will actually fade when exposed to sunlight over a period of time.

Heat Treated Carnelian

A simple way to test if your beads have been dyed is to lick your fingers and then run them over the stones. Any residue dye will come off on your fingers. A better way is to rub nail polish remover over the beads to see if the dye comes off.

At BeadShopUK we actually make sure any dyed beads do not run once worn by soaking them in hot soapy water, and then soaking them in Acetone. Thankfully we've had no complaints so far (touching wood!)

The second most common treatment is exposure to heat. Certain stones can undergo drastic colour change when heated to a high temperature. The result can be a brighter colour or a deeper shade. Have a look at the Carnelian beads as an example.

Heat treatment is relatively stable and the colour change will last a long time. It’s also not possible to detect whether the stone has been treated with heat by nail polish remover.

Other modern methods for the treatment of gemstones include:

• Bleaching – which is almost impossible to detect
• Surface Coating – used mainly in the Gemstone industry on faceted stones
• Fracture or Cavity filling – used mainly on precious stones (diamond, ruby, emerald) to improve clarity.
• HPHT Treatment – High Pressure High Temperature, used on Diamonds
• Impregnation - the surface of a porous gemstone is permeated with a polymer, wax or plastic to give it greater durability and improve its appearance. This is a common treatment for Turquoise beads, as without it the stone would naturally disintegrate with day to day use.
• Irradiation - exposure of a gem to an artificial source of radiation to change its colour.

CONCLUSION

All good bead and gemstones suppliers should always disclose if the beads have been treated, but in reality many don’t. Sometimes it’s simply because they don’t know how the stone has been treated. Other times they prefer not to tell their customers.   

In the end however it's a matter of choice. Some customers prefer only natural colours and will avoid dyed stones like the plague. Others will be attracted to the variety of colours on offer and don't care that they have been treated.