JET 557 



A coal having the properties enumerated above is described as a pitch-coal. From 

 ordinary pitch-coal of frequent occurrence, which is usually very brittle, jet is distinguished 

 by its greater toughness and firmness, and by the fact that it can be worked for ornamental 

 articles. Coals which possess the characters detailed above in a more or less perfect degree 

 are found at various localities, and at these places the principal jet- working establishments 

 are situated. 



The principal and, indeed, the only jet-cutting works in England are situated at 

 "Whitby, on ^the Yorkshire coast. There are but few establishments of the kind on the 

 continent, and compared with the importance of the Whitby industry they are quite 

 insignificant. Whitby has, therefore, the same importance in England, as the centre of the jet- 

 cutting industry, as Oberstein has in Germany as the centre of the agate-cutting industry. 

 The hard jet of Whitby appears to have been used in Britain in pre-Roman days; it 

 is alluded to by Caedmon, and mentioned in 1350 in the records of St. Hilda's Abbey. It 

 was formerly extensively mined in the cliffs of the Yorkshire coast, near Whitby, and 

 elsewhere ; in Eskdale, Danby Dale, and in several of the dales that intersect the East 

 Yorkshire moorlands. The hard jet occurs in the black shales of the Ammonites 

 serpeniinus zone of the Upper Lias, frequently in the form of flattened masses or layers, 

 which in rai'e cases have been found to reach a length of 6 feet. So rich are these black 

 shales in jet that they are often referred to as the jet-rock. The richest deposit is at 

 Robin Hood's Bay, four miles south-east of Whitby. 



A considerable amount of material is annually obtained, the yield in the year 1880, 

 for example, being 6720 pounds. Two qualities of jet are worked at Whitby, a harder and 

 better quality ranging in price from ^s. to 21s. a pound, obtained for the most part in the 

 neighbourhood, and a softer, poorer, and cheaper quality, which is imported in large 

 quantities from Aragon in Spain. The value of the jet-goods turned out by the Whitby 

 works yearly amounts to about ^100,000; in the year 1855 it amounted to ^20,000. 

 Between 1200 and 1500 persons are engaged in England at the present time in this 

 industry. 



At Whitby is also worked another substance which is of English origin and similar to 

 jet, namely caniwl-coal. This is of a greyish or brownish-black colour, less brilliant, less 

 susceptible of a good polish, and more brittle than jet. It is found in large masses in the 

 Coal Measures at Newcastle, and other places in England and in Scotland. Owing to its 

 occun-ence in large masses, this substance can be used as a veneer for surfaces of considerable 

 size, this being impossible in the case of true jet. 



Jet occurs and is worked in certain parts of the Continent. The rough material 

 obtained in Spain is exported to England, the jet- working industry which once flourisiied 

 there having now almost died out. The jet localities are situated in Aragon, Galicia, aind 

 Asturia, and what is done in the way of working the material is performed at several 

 places in Asturia. 



In France the material occurs in the greensand of the Cretaceous formation in the 

 department Aude, province of Languedoc, where also an ancient jet-working industry once 

 flourished. As in Yorkshire the jet occurs as thin plates, which rarely reach a weight of 

 15 pounds. The chief localities are Monjardin, near Chalabre, on Mount Commo-Escuro, and 

 Bugarach, on Mount Cerbeiron, where mining was carried on, though not systematically. 

 An additional supply of rough material was obtained from Spain, and it has been stated 

 that some of the Spanish jet is superior in quality to the French. 



The jet-working industry flourished in France in the eighteenth century, and in the 

 year 1786 there were 1200 people employed in it, principally in the communities of 



