554 SYSTEMATIC DESCRIPTION OF PRECIOUS STONES 



but, owing to its brittleness, it cannot well be bored, nor a screw cut on it. For the same 

 reason articles made of gedanite must be handled withgreat care. In consequence of thes e 

 disadvantages the different kinds of gedanite are not worth more than a third of the value 

 of corresponding qualities of amber. No distinction is made in the trade between articles 

 made of succinite and those made of gedanite, and the services of an expert are requii-ed 

 when it is necessary to determine whether a given article is made of gedanite or of 

 true amber. 



The occurrence of gedanite is confined to the amber-diggings of the Prussian coast. 

 The material is found in small amount wdtli dug-amber, but never with sea-amber, 

 probably because it is too brittle to resist the battering of the waves and the pebbles of 

 the beach. 



ROUMANIAN AMBER. (ROUMANITE.) 



Roumanite, or Roumanian amber, is rarely yellow, but is usually brownish-yellow to 

 brown. It is transparent to translucent, and scarcely ever opaque. Fluorescent specimens 

 are sometimes met with, finer even than Sicilian amber, which is regarded as fluorescent 

 amber par excellence. A characteristic feature of Roumanian amber is the presence 

 of numerous cracks, which, however, do not seriously affect the cohesion of the material. 

 Notwithstanding the fact that many of these stones are quite full of cracks, they 

 can be turned, cut, polished, and otherwise worked without being broken. The substance is 

 brittle, and has a conchoidaj fracture. When rubbed it acquires a charge of negative 

 electricity. The hardness slightly exceeds that of true amber. Succinic acid is present in 

 variable amount (up to 3"2 per cent.), but on an average in less amount than in Prussian 

 amber. The presence of a comparativelv large amount of sulphur amounting to 1'15 per 

 cent, in roumanite is a characteristic feature. The substance offers a still greater resistance 

 to solvents than amber. When heated it gives off a peculiar aromatic odour, and at the 

 same time a smell of hydrogen sulphide (like the smell of rotten eggs), which is due to the 

 presence of sulphur. It fuses at 300° C. without swelling up, and gives off fumes, which 

 act as an irritant on the respiratory passages. 



This resin occurs enveloped in a closely-adhering, weathered crust, which is always 

 very thin, and of a dark yellowish-grey to reddish-brown colour. It is found as nodules in 

 carbonaceous, laminated shales, or as interrupted layers in sandstone beds in the district of 

 Buseo. At Buscou, on the railway line from Bucharest to Braila, it is found within a radius 

 of about a mile in the earth on common-land ; while at Valeny di Muntye rounded 

 fragments are found among the pebbles of a brook. The strata in which I'oumanite occurs, 

 or in which it originated, belong to the later Tertiary period (the Congeria beds). Most of 

 it is sent to Vienna, whei-e, under the name of " Roumanian amber,'" it is manufactured into 

 cigarette-holders and other useful or ornamental articles. To a certain extent it entei'S 

 into competition with Prussian amber, but, owing to its comparative rarity and higher price, 

 this competition is not serious. 



The substance known in Roumania as " black amber " is not amber at all, but jet, a 

 variety of coal which will be considered presently. 



