'AB' stands for Aurora Borealis, the amazing natural light display in the sky, particularly in high latitude regions around the Arctic and Antarctic...
It was a name Swarovski used in partnership with Dior in 1956 to describe the effect achieved when a very thin layer of gold was vacuum-coated onto the surface of crystal. The play of facets, reflections and colours of this coating made an effect similar to viewing the Aurora Borealis...beautiful, shimmering and rather ethereal.
As more companies added the technology to their ranges, the term became widely used and today it is shortened to the somewhat less glamorous 'AB' term you see after such colours as Crystal, Emerald, Rose for example (which become crystal AB, Emerald AB and Rose AB).
But AB effects are not always the same...
There are many factors that change what you'll see from one crystal to the next. In other words, as varied as the Aurora Boreale can be, the effect of the AB coating can also be very varied. For example, AB coating applied to light colours produces an effect which is subtle, luminescent and soft, similar to the soft colours seen on the surface of bubbles in certain lights - pinks, soft green, soft blue, soft yellow.
But, put the same AB coating on a dark colour such as Jet, Siam or Emerald, even Fuchsia or Amethyst, and you will get quite a different effect. On dark colours the AB coating takes on a brighter hue where the gold is more visible as gold and a metallic light aqua blue can be seen. With the dark colour under the coating there is less 'see-throughness' for the coating to be reflected through and the coated surface is not diffused by the transparency of the crystal underneath.
However, as most clients will testify, often an AB coated stone will take on the colours around it, such as the colour of the fabric it is glued to, and the other stone colours around it. That is why we always advocate using a colour stone and a colour AB stone to get, well... colour, and AB!
The amount of AB coating can also make a difference...
In our experience, Swarovski tend to coat quite thickly, so on darker colours the yellow and aqua highlights of the AB coating can be quite pronounced. A 'Sapphire' stone for example will look very 'Sapphire', while 'Sapphire AB' can look a lot like a super sparkly 'Aquamarine'.
Preciosa tend to coat with a more light-handed approach, which allows the colour of the stone (light or dark) to come through the AB coating more readily. So 'Sapphire AB' for example does tend to allow more of the true 'Sapphire' colour to be come through as well as getting that delightful twinkle from the AB.
If only life were simple and we could pigeon-hole AB coatings, but even as photographic images of the Aurora Borealis testify to the differences inherent in such a light display, so too is the way the human eye captures the effect of AB coating from one colour to the next, under one set of lights to the next, in one photo to the next...
Then there's 'half coating' (known as 'AB') and 'full coating' (known as 'AB 2x')...
All beads that are AB coated are 'half-coated', which means that half the crystal is coated, and half is not. In the case of flatbacks, the entire top surface is coated, while the entire underside surface is not (it is usually silver-foiled).
The 'full coating' is offered on some beads and pendants, though not many, and increasingly less over the years. If it is full-coated (eg; Light Rose AB 2x) the entire surface of the crystal is coated with the AB finish. This makes an amazing effect, especially on light coloured crystals, but due to their relative scarcity standard 'half coating' is the kind of crystals that we are all most familiar with.
Underside 'foiling' vs 'non-foiled' also make a difference...
Now depending on whether an item is silver foiled on one side (eg; flatbacks/pointbacks on their underside) or whether it is completely see-through, such as a clear bead, the AB coating can also look very different. On the first, with the silver foiled underside, the AB coating not only has the facets of the crystal to reflect itself within, it has the added benefit of the silver-foiling which acts as a mirror for the AB coating to reflect back up into the many stone facets also.
There is a lot going on in the one stone, as we say, hence the tremendous sparkle and movement that the AB coating can add to flatback stones. Glorious for stage and performance situations where maximum sparkle and glamour is required.
Where an item is not foiled at all the AB coating will be more subtle, as the overall effect will remain 'see-through' in the absence of any foiling, yet because of the AB coating the crystal will still glint and glisten in a way that a non-AB coated crystal simply can't.
So, is AB for you?
To AB or not to AB, that is often the question... Understanding AB coatings will help you to know if it's right for you and the application you need your crystals for. If the book-that-we-could-practically-write (!) about AB coatings has helped but you still need some more targeted advice, feel welcome to contact us by email, phone or on facebook.
We'll be happy to help!
Donna & the team at Rhinestonz & Beads