Bohemian glass sometimes referred to as Bohemia crystal, is glass produced in the regions of Bohemia and Silesia, now parts of the Czech Republic. It has a centuries long history of being internationally recognised for its high quality, craftsmanship, beauty and often innovative designs. Hand-cut, engraved, blown and painted decorative glassware ranging from champagne flutes to enormous chandeliers, ornaments, figurines and other glass items are among the best known Czech exports and immensely popular as tourist souvenirs. The Czech Republic is home to numerous glass studios and schools attended by local and foreign students.
Oldest archaeological excavations of glass-making sites date to around 1250 and are located in the Lusatian Mountains of Northern Bohemia.

Jug in Bohemia, Karlsbad (Karlovy Vary) by L. Moser & Sohne
http://en.wikipedia.org/wiki/Bohemian_glass

Crystal vs. glass

In the Czech Republic, the term "crystal" is used for any exquisite, high quality glass. Leaded crystal means crystal containing more than 24% lead oxide.

In the European Union, only glass products containing at least 24% of lead oxide may be referred to as "lead crystal".

In the USA it is the opposite - glass is defined as "crystal" if it contains only 1% lead.

History

Bohemia, a part of the Czech Republic , became famous for its beautiful and colourful glass during the Renaissance.

Bohemian glass-workers discovered potash combined with chalk created a clear colourless glass that was more stable than glass from Italy.
During the era, the Czech lands became the dominant producer of decorative glassware and the local manufacture of glass earned international reputation in high Baroque style from 1685 to 1750.
Czech glassware became as prestigious as jewellery and was sought-after by the wealthy and the aristocracy of the time.
Today, Czech crystal chandeliers hang, for example, in Milan's La Scala, in Rome's Teatro dell'Opera, in Versailles, in the Hermitage Museum in St. Petersburg or in the royal palace in Riyadh. Various sorts of glassware, art glass, ornaments, figurines, costume jewellery, beads and others also remain internationally valued.

Reverse glass painting was also a Czech specialty
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Czech costume jewelry

It was in glass center of Gablonz, at the end of the Victorian Era, that Austrian jeweler Daniel Swarovski introduced the first cut-glass crystals to successfully imitate the look of diamonds, rubies, sapphires, and emeralds. In 1892, Swarovski patented a mechanical glass cutter so his crystals could be mass-produced to meet the high demand.

Bohemian costume jewelers also pioneered a technique for replicating the look of pearls, which were enormously popular at the beginning of the 20th century.But glass remains the Bohemia region’s most important contribution to costume jewelry.

Amethyst Czech Glass Bracelet 1920s

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Art Deco Bracelet Amber Glass

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Druk

One of the glass items for which the Czech nation is still well known is the production of "druk" beads. Druks are small (3mm-18mm) round glass beads with small threading holes produced in a wide variety of colors and finishes and used mainly as spacers among beaded jewellery makers.