Jet has been used used in jewelry in Europe since 10,000 to 17,000 B.C. , though it is more often associated with Queen Victoria’s mourning dress after the death of Prince Albert. While many think of Whitby jet, it is found in a variety of places and has even been used by the Anasazi Tribe in America. There are many substitutions for real jet, the most common being glass, though hard rubber , ebonite or vulcanite, bakelite coal, epoxy resins have all been used in the past.
The Romans used jet in jewelry during much of their 367 year of occupation (43 AD to 410 AD) of Britain. Roman workshops dotted the landscape where it was found. believing it deflected the evil eye with it’s mystical properties. As a result it became popular for use in hair pins, bracelets, brooches, rings, pendants, dagger handles and other jewelry. Most was exported from Eboracum (York) all other Roman Britain and Europe. After the Romans left Britain the use of jet in jewelry declined. It is interesting to note that when an excavation of a Eboracum (York) railway station foundations occurred, an entire Roman workshop was discovered for Jet!
Jet shows up in the Medieval Ages mainly for the use in rosaries. It next became fashionable in the Victorian Period after the death of Prince Phillip. Whitby Jet for carved in many forms and pieces of jewelry then, but they 1920 the craft had declined once again. Glass was also molded to form a suitable substitute, as well as other materials by then, as it was in such demand.
Jet is know by many names. In French “jais” or “jaiet”; in Spain “azabache” which come from a moorish word “cebeche” meaning “Black stone”. The moors wore a jet “higa” or phallic hand to protect them from the evil eye, it continues in places to this day.
Jet is not actually a “stone”, or true mineral, but a mineraloid. It comes in two forms “hard” and “soft” jet. Hard jet is the result of carbon compression and salt water. Soft jet is the result of Carbon compression and “fresh” water. It is due to the anaerobic fossil of the tree Araucaria cells which have been flatten by huge pressure (compression) over time and subjected to chemical changes. This process started during the Jurassic Period 150 to 180 Million years ago.
Jet has a:
- refractive index of 1.64 – 1.68
- specific gravity 1.3 -1.4
- Mohs scale 2.5 – 4 .0
- Carbon 75.2 %
- Hydrogen 7.0%
- Nitrogen 0.7%
- Sulphur 4.6 %
- Oxygen 12.5 %
Whitbey Jet also contains other proportions of aluminium, though Spanish jet has a higher percentage of sulpher.
detail of 1950’s “jet” glass beads
To tell if Jet is REAL;
- jet is warm to touch, glass is cold
- jet is light
- jet leaves a brownish color streak on unglazed porcelain
- jet will smell like coal when burnt with a red hot needle..be very careful as jet does burn
- jet can exhibit a static electricity charge if polished.
- jet may contain imperfection such as tiny cracks or inclusions.
- Jet is black.
- Jet will look hand carved, NOT CAST or MOLDED!
mark on unglazed porcelain.. note some other materials will also do this, but the hot pin test emits a “coal” smell, but must be done carefully as jet will burn.
For jet and other vintage and antiques:
No comments:
Post a Comment