be successfully imitated. It is said that 

 the Romans were able to make artificial 

 Opals closely resembling the real, but, 

 if so, the art has been lost never to be 

 recovered, and we may hope it never 

 will be. Hence, however much danger 

 there may be m buying an Opal that it 

 has not been properly "seasoned," or 

 may not retain its color, the purchaser 

 may at least be sure he has an Opal and 

 not an imitation. The stones are usually 

 cut in the oval form known as en ca- 

 bouchon, this cutting being found to 

 bring out their brilliancy better than any 

 facetted form. The brilliancy of the 

 stone may be increased in setting by giv- 

 ing it a backing of mother of pearl or 

 bla';.k silk. When a number of Opals 

 are placed together they seem to bor- 

 row brilliancy from one another, a fact 

 which is taken advantage of in settings 

 by placing a number together and also 

 by Opal dealers to dispose of inferior 

 stones by grouping them with good ones. 

 For this reason when Opals are pur- 

 chased they should be examined sepa- 

 rately. The value of Opals depends al- 

 most wholly on the brilliancy of their 

 colorinji- and their size. Stones without 

 the play of colors are practically worth- 

 less, while stones of ten to twenty 

 carats' weight, with brilliant coloring, 

 may bring several hundred dollars. The 

 most highly valued Opals have long come 

 from the mines of Czernowitza in north- 

 ern Hungary. These Opals are often 

 known as Oriental Opals from the fact 

 that in early days they were first pur- 

 chased by Greek and Turkish mer- 

 chants, and by them sent to Holland. 

 There are, however, no localities in the 

 Orient where precious Opals are found. 

 The rock in which the Hungarian Opals 

 occur is eruptive, and of the kind known 

 as andesitc. It is considerably decom- 

 posed, and the Opal occurs in clefts and 

 .veins. There is little doubt that it was 

 fiom these mines that the Romans olv 

 taincd the Opals known to them, and 

 the ()nt])ut has been quite constant since. 

 It is said that the Hungarian Opals arc 

 less likely to deteriorate than any others. 

 Still the danger of deterioration is not 

 great in any Opal. The other important 

 countries from which precious Opals arc 



obtained are Mexico-, Honduras and Aus- 

 tralia. The Mexican Opals are mostly 

 of the fire Opal variety. They are 

 mined in a number of the States of the 

 Republic — Queretaro, Hidalgo, Guerrero, 

 Michoacan, Jalisco and San Luis Potosi. 

 The oldest mmes are in the State of 

 Hidalgo, near Zimapan, where the Opal 

 occurs in a red trachyte. Most of the 

 Mexican Opals on the market at the 

 present time, however, come from the 

 State of Queretaro, where mining for 

 them, is conducted on a more extensive 

 scale. The Opal here occurs in long 

 veins in a porphyritic trachyte, and is 

 mined at various points. The stones are 

 cut and polished by workmen in the city 

 of Queretaro who use ordinary grind- 

 stones and chamois skins for the work 

 and are said to receive an average wage 

 of 23 cents a day. 



The Honduras Opals reach foreign 

 markets but rarely and usually uncut. 

 The mines are in the western part of 

 Honduras, in the Department of Gracias. 

 They are little worked, but there is no 

 doubt that extensive deposits exist which 

 might afford a good supply of gems if 

 they were properly exploited. The Aus- 

 tralian Opals come from several locali- 

 ties, the most prominent at the present 

 time being White Cliffs, New South 

 Wales. The matrix is a Cretaceous 

 sandstone which has been permeated by 

 hot volcanic waters. Shells, bones and 

 Other fossils are found here entirely 

 altered to precious Opal, making objects 

 of great beauty. In 1899 Opals to the 

 value of $650,000 were sold from this 

 single region. There is no doubt that 

 the present popularity of the Opal is 

 due to some extent to the supply of 

 beautiful stones which has come from 

 tliese mines at prices at from one-third 

 to one-tenth those of the Hungarian 

 stones. Other localities in Australia 

 whence precious Opals are obtained are 

 places on the Barcoo River and Bulla 

 Creek, Queensland, and occasional finds 

 in West Australia. 



No localities in the United States 

 voiding ])rccious Opals in any quantity 

 liavc yet l)een discovered. Some good 

 stones have hccn cut from an occur- 

 rence in Idaho, and some other minor 

 liiids have been made, but they possess 



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