74 The Production and Generation 

 Hone, which take up a large compafs, but alio in 

 peculiar fmall feams and veins, travcrfing fuch 

 large /rata, often various layers are obfervable. 



Of this miniature fat-work ftone, if I may fo 

 call it, we have an extraordinary inftance, at Fri- 

 berg, in the uncommon jafper, or coral ftone. 

 For, there we have (i.) a white, heavy fpad. 

 Under this (2.) a fmooth mountain-cry ftal, both 

 of them from 1 to 2 inches thick. (3.) Amethift. 

 (4.) Again, mountain-cryftal, or quartz. (5.) Jaf- 

 per. (6.) Mountain-cryftal. (7.) Jafper. (8.) 

 Mountain-cryftal. (9.) Jafper. (10.) Cryftal. The 

 former eight layers are often only the thicknefs of 

 a fine thread, and all together fcarce exceeding 

 I inch, and yet very diftincl:. (11.) Jafper, of a 

 bright red. (12.) Jafper, of a dark red. (13.) 

 Chalcedon. (14.) Jafper. (15.) Chalcedon ; nay, 

 the two laft, once or twice more, alternately. (16.) 

 A firm horny quartz. The laft fix or eight grow 

 ftill thicker and thicker, the jafper there being 

 often an inch thick, and above. Thefe layers of 

 precious ftone, which are extremely beautiful to 

 the eye, cohere very firm and clofe together, fo 

 that the entire ftone bears fplitting tranfverfely, 

 better than in the feams ; and then they lie not fo 

 flat in fhivers on each other, but vaulted one over 

 the other, with fmall arches, fo that the thickeft 

 layer of jafper may be clearly feen to traverfe molt 

 of the upper layers, till, at length, it gradually 

 lofes itfelf : yet there the jafper-layers are moil 

 ealily feparable where thickeft, alfo where the chal- 

 cedon is thickeft : and as it there exhibits pure 

 round eminences, ftanding clofe to each other, 

 like fo many little balls cut afunder, whofe con- 

 cavities lodge in the chalcedon, it is here, at Fri- 

 berg, commonly called coral-ftone. In particular, 

 the violet call: of the amethift, and the red blufh 

 of the jafper, whereby it comes to refemble coral, 



would 



