One consideration when purchasing a chandelier is the quality of the crystals it has onboard. With jewelry, the quality of the gems incorporated into the ring or necklace gives off a message independent of the jewelry design. So it goes with crystal and chandeliers. As with everything in life, there are grades of crystal quality, and -- as with most things -- you pretty much get what you pay for.
WHAT’S CRYSTAL MADE OF?
At root, crystal is comprised of silica (sand), potash and lead oxide. Lead oxide is added to a basic glass mixture for a refraction effect. Leaded glass contains from 5-20% lead content. Leaded glass is typically used in churches and for certain applications in older homes. It is typically not used in contemporary window-treatments but the formula is used in cheaper crystal. Traditionally, once the lead content gets above 20%, it is considered crystal, though these days the definitions of "leaded glass" and crystal have become blurred. The optimal lead content for crystal is between 20 and 30%, which allows for greatest refraction of light. It should also be noted that lead oxide is no longer the only additive which can produce refraction. Because of restrictions on lead content in the last twenty years by both California and The European Union, a number of crystal manufacturers have introduced "lead-free" crystal, which contain different additives, such as barium, zinc, or potassium oxides.
A higher lead content tends to make crystal more fragile, but this is less of a problem for chandelier crystals than it is for other types of crystal (decanters, stemware, etc.), which need to be more robust because they are regularly handled. Once the chandelier crystal is in place, fragility shouldn’t be much of a problem (assuming that you’re not regularly swatting insects or bats anywhere near your chandelier). But lead content is only one of the factors that indicate crystal quality. The care taken during the manufacturing process of crystal is perhaps even more important in determining quality than the raw ingredients.
WHAT TO LOOK FOR WHEN BUYING CRYSTAL
Crystal is a type of glass, and is made, essentially, in the same way -- by heating the ingredients to a molten form. It is then poured into molds which give the chandelier crystal its shape. A great deal of care has gone into figuring out the faceting of each crystal, as a thoughtful design will yield greater refraction of light.
Left to itself, leaded crystal will cool like a cake: the outer part cools quickly, and the inner core takes longer to dissipate heat. That differential in temperature means that the inner parts of the crystal cool off later than the outer parts, and that can leave very fine striations in the crystal. You probably wouldn’t notice them on first glance — you might even mistake them for fingerprints. But those tiny striations can distort the light passing through the crystal. Once you notice them, they will be hard to ignore. Cheaper crystal is made without any control of the cooling process, and can therefore show these subtle distortions. The other thing to watch out for is bubbles. Cheaper crystal can often have a tiny bubble or two trapped inside. Once you see a bubble, you can't un-see it.
Crystal is very seldom branded, and often there's no information on the provenance of the crystal on the chandelier you are about to buy. And if you are buying a particular chandelier, you will probably buy it because you like its design, and will have to take the crystals, whatever they may be. Still, good quality crystal is worth knowing about, and here are some tips to keep in mind:
MAKE SURE IT'S CRYSTAL, NOT ACRYLIC OR GLASS
Most people should be able to spot acrylic right away: If you are looking at a "crystal" chandelier at Home Depot and it costs $50, those crystals are almost certainly plastic. Acrylic is really light and has a dull finish, poor clarity, and unsharp faceting. Glass is a step-up from clear acrylic, obviously, but has none of crystal's refractive qualities. It's just, well, glass.
Because this is a cheap solution, glass "crystals" are generally poorly made, with little sharpness to the faceting, poor polish, and you will often see bubbles inside. If you are reading this, you care enough about quality to avoid both of these options like the plague.
K5 OR K9 BOROSILICATE GLASS ("CHINESE CRYSTAL")
This is the most common type of "crystal" that you'll see out there. If the fixture itself was made in China, it is overwhelmingly likely that the crystal will be of this type. Borosilicate glass is not, strictly speaking, crystal, as its lead content is below 10% (the original terms "K5" and K9" refer to the percentage of lead oxide content -- 5% and 9% respectively). K9 glass should be considered to be a higher quality than K5 glass.
K9 glass is popular for a number of reasons: It is relatively cheap to make compared to real crystal; it has a relatively high refractive index and pretty good clarity properties. This type of glass can be polished as highly as crystal can be. Additionally, because most mass produced lighting worldwide is made in bulk in China, it makes sense that those fixtures would ship with K9 glass -- an inexpensive option that is manufactured locally.
If you are buying a crystal chandelier or pendant for under, say, $1,500, the chances are that the crystals will be either K5 or K9 Borosilicate glass. Consider K9 to be the Toyota Camry of chandelier glass: relatively cheap, reliable, ubiquitous -- it gets the job done. But given that your chandelier is the jewelry of your home, you may want to consider spending a little more to get something considerably more exquisite.
GEM CUT CRYSTAL
Gem cut crystal generally refers to high quality, "real" crystal, between 24% and 34% lead oxide. There are gradations of quality points within this category, such as optical purity, and polish. Optical purity has to do with minimizing the distortion of light passing through, and the best way to do that is to control the cooling process of the molten crystal.
Once molten crystal is poured, it cools much like a cake from the oven: The outer parts cool down first, and the innermost center cools last. With crystal, those temperature variations can cause tiny striations -- kind of like fingerprints in the middle of the crystal. To prevent this, manufacturers have learned that they can apply heat to the cooling process so that the outer portions of the crystal cool at roughly the same rate as the core. Obviously, this can get a little tricky and adds to the manufacturing cost of the crystal.
Other variabilities in quality include the sharpness of the faceting and how highly polished the surface of the crystal is. Some manufacturers will include a semi-precious metal coating, which can protect the crystal's polish. At Michael McHale Designs, our standard crystal is optically-pure, sharply faceted, and highly polished.
Ireland's contribution to the world of crystal is the venerable Waterford Company. They mostly make glass wear but do sell very traditional chandeliers made with their signature crystal. Waterford is known for their wood mold technique of making crystal, which requires a great deal of craftsman skill and attention to detail. Waterford does not currently sell their chandelier crystal as parts to third-party artisans, so the only place you really get Waterford chandelier crystal is on Waterford chandeliers.
Murano glass is often mentioned in the same sentence with some of the finest chandeliers in the world, and it's confusing to realize that Murano glass is not, strictly speaking, crystal. It is blown glass from Murano, Italy, an island adjacent to Venice. Over the centuries the master craftsmen of Murano developed a number of glass blowing techniques that are still used today. Technically, only glass blown on the tiny island of Murano itself can be called Murano glass, though you wouldn't know it from the widespread abuse of that term amongst unscrupulous marketers.
Rock cut crystal is naturally occurring clear form of quartz that is mined from the earth. Rock crystal isn't optically pure, and you wouldn't want it to be. It is full of veins and natural occlusions, all of which makes it all the more interesting. Rock crystals themselves tend to be thick and bulky, and are often paired with very traditional chandeliers -- true to the time and place where rock crystal was originally quarried: in the Bohemia section of central Europe in the Eighteenth Century.
Chances are if you have heard of any “brand” of crystal, it’s Swarovski. They seem to be everywhere these days. Their crystal provides the industry-standard in terms of optical clarity, and giving a high refractive index. Additionally, Swarovski adds a layer to the surface of their crystal making it slightly more dust-resistant than regular crystal. Swarovski recently opted out of lead oxide for its crystal and now relies on a lead-free formula.
At Michael McHale Designs, we love Swarovski crystal. It is without a doubt some of the finest crystal parts available. The only downside to Swarovski crystal is, of course, the price: Having a chandelier with 100% Swarovski crystal can easily double the price of your chandelier or fixture. If price is no object, or if you have a particular interest in the resale value of the piece, Swarovski is the way to go.
Michael McHale Designs can make any of our fixtures with Swarovski crystal as a special order. Most of our customers, though, opt for our optically pure gem-cut crystal. This crystal is also 30% leaded for maximum refraction and also optically pure – just without the Swarovski brand name. It would take a very sophisticated eye to tell the difference. A note on our colored crystal options (which Michael McHale Designs offers as a custom option): When it comes to colored crystal, Swarovski has no peer in terms of clarity and brightness. So if you order colored crystal from us, it will always be Swarovski.
Like Waterford, Baccarat makes its own chandeliers, both traditional and modern, with its own handmade crystal. They make their crystal by hand through an exhaustive, time-intensive process. Baccarat is the byword for expert craftsmanship. The number of inspections that each crystal undergoes to make sure it is defect-free is staggering. If Swarovski is the Ferrari of the crystal world, Baccarat is the McLaren.