Czech glass and Czech crystal
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Czech Glass and Czech Crystal - What's the difference?Let's first define what is Czech crystal and that will make Czech glass (and it's different types) a bit more understandable. There's a difference between the EU and USA on this and you'll need a Chemistry degree to fully understand it all but here goes:
For something to be called Czech crystal it must contain at least 10% lead oxide. European standards demand that to be called "Leaded" Czech crystal it must have at least 24%. High end Czech Crystal production may be labelled as "high leaded" Czech crystal indicating that it has lead content greater than 30%. Czech crystal labelled as "full-lead" meets the 24% standard. Crystal can be less than 24% lead content if it contains enough of an element called Barium which increases the optical qualities.
Glass always has trace elements of lead but in the USA the lead content need only be as little as 1% to qualify it to be called crystal. Compare this to the EU where anything with less than 4% lead is glass.
Czech Glass and Czech Crystal - How do I know if it's Crystal or Glass?Two things will identify Czech crystal. The first is the weight. 24% lead content makes crystal much heavier than Czech glass. Cheaper products will increase the glass volume for cutting making it much thicker and making the weight heavier which brings us to the second identifier. Real Czech crystal has optical properties which have to be seen to be believed. Holding a Czech crystal glass up to even normal light should result in "multiple rainbows" as the lead content increases the light refraction properties it's like looking into hundreds of prisms simultaneously.
Czech Glass and Czech Crystal - Is cut glass and cut glass crystal the same?As described above, Czech glass on it's own can be very attractive after it has been cut into various designs but it does not have the light refraction properties of cut crystal. Cut glass can also be called "faceted" which is the method of cutting angles into the glass to increase refraction properties.
Czech Glass - Coloured or Painted GlassThree hundred years ago it was difficult to produce completely clear Czech glass free of impurities. The producers decided to adapt their products to a bigger market and address the impurity problem by using coloured glass. There are four main colour groups, Red, Blue, Green and Brown. Blue and Green Czech glass are the famous products of the former Czechslovakia renowned worldwide over the last two centuries. The other colours are more recent. As a rule you don't normally find coloured Czech crystal as coloured glass does not refract light. This is also known as "Stained" Czech glass.
The glass can be clear but normally it's an add-on for coloured (can also be called "enamelled") Czech glass. The designs very wildly in terms of the subject, the amount of surface covered and thickness of the enamelled paint. The most popular Czech glass colours for painting are red and green. The most popular designs are flowers. I have to say that painted Czech glass sets of glasses look great in the shop but, take a minute to imagine how and where you would use them when you get home. Clear glass is timeless, colour clashes. And don't even think about putting these things in the dishwasher.