574 REPORT OF NATIONAL MUSEUM, 1893. 



even up to L'O feet in length by 4 feet square. At this date it is stated 

 bhicks may be liad 10 feet in length by 3 feet in width and thickness. 

 The second deposit noted, called ArdJa-el-Beida, lies some 3 kilometers 

 to the west of Bled Bekham, upon a plateau Avitli steep north, west, 

 and south escarpments. It was once continuous with a bed called El 

 Cellon, but from which it has become separated by a ravine called the 

 Chabbat-Karonba. The onyx of this locality is said to be inferior to 

 that of the first, both as regards quality and size of blocks obtainable. 

 The beds vary in thickness from 30 inches with a total of some 10 feet, 

 and cover an area of about 20 acres. All the deposits are Quaternary, 

 and lie unconformably upon lime and sandstones of Tertiary (]Middle 

 Miocene) age. The stone, as is usually the case, varies greatly in color 

 and shade, from jjure white to rose-colored and bright red, golden yel- 

 low, and, more rarely, green. The present quarriers (Sauville & Co., 

 Paris) divide the output into four classes, le Blanc, le Ruhaune ov Yeine^ 

 le Cacheniire and le Cachemire hois. The white (blanc) variety is the 

 more abundant, and is found in nearly all the quarries, occurring in 

 layers sometimes upward of a meter in thickness, and blocks have 

 been removed containing upwards of 5 cubic meters. It varies from 

 translucent to opaque, sometimes milk white or veined with fine ribbons 

 of pale yellow. The milk-white variety is employed for columns, arti- 

 cles used in religious ceremonies, and in place of ordinary white marble 

 in furniture. The translucent variety is employed in statuary, and has, 

 besides, many other applications, as for the glazing of church windows 

 and for shades. The ribboned or veined onyx is also abundant, and 

 there are many places for its extraction. The ribbons are parallel with 

 the plane of deposition, and of a clear deep yellow, sometimes rose or 

 violet tint. Other irregular veins traverse the stone in all directions, 

 giving very beautiful effects. This variety is also obtainable in blocks 

 of good size, and is used for buildings, columns, pilasters, balustrades, 

 stairways, panels, or for furniture tops. A green variety also occurs, 

 though now somewhat sparingly. The prevailing color is paler than 

 the better varieties of the Mexican or American stone. A rose variety, 

 said to have been especially admired by the Romans, is found in small 

 blocks, scarcely larger than a paving stone. White translucent varieties 

 with irregular veins of lively red or orange yellow also occur, though 

 sporadically and in small masses.* 



*Iu a publication entitled "Notice Mineralogique par la Service des Mines" 

 (Algeria, 1889) I find references to onyx quarries as below: In the province of 

 Oran, at Ain Seboa, some 17.5 kilometers south 32° west from Nemours, an onyx of 

 yellow, gray, and vermilion tint, apparently belonging to the Quaternaiy period 

 and resting upon Oxfordian beds; at Sidi Brahim, 10 kilometers south 4° west of 

 Nemours, a similar stone, but of poorer quality, and at Tekbalet, 26 kilometers north 

 21- east from Tlemcen, a very beautiful variety of diverse hues intercalated in isolate<l 

 Quaternary areas resting upon Miocene; in the province of Coustantiue, in Oued 

 Zergua, some 40 kilometers southeast of Souk-Ahras, a marble approximating onyx 

 occurring in veins in Ceuomanieu beds. This doubtless a stalagmitic or stalactitic 

 deposit. 



