37 
TAB. CCXIX. 
SILEX Quartzum; var. Jaspis. 
Jasper. 
Class 2. Earths. Order 1, Homogencous. _ 
Gen. 4. Silex. Spec. 1. Quartzum. 
Div. 1. Crystallized, 
Syn. Iron Flint. Jameson, v. 1. p, 134. 
Eizen Keisel. /WVerner. 
a 
Tus has an appearance so peculiar, that it may be readily 
distinguished when once seen, although on careful exami- 
nation it will be found to differ very little, if at all, from 
the other coloured Jaspers, either in its nature or compo- 
nent parts. It is said to be crystallized, like Quartz, with 
the pyramids terminating in three faces, and sometimes 
with the other three belonging to Quartz very small *. The 
fact is, that this substance is no other than Quartz with a 
red or yellow Oxide of Iron, and is often partially crystal- 
lized, though sometimes otherwise with an appearance 
rather peculiar, which occasionally resembles a coarse red 
sealing-wax, or the cement used by lapidaries, made of 
pitch, resin, and brick-dust. Its hardness is the same as 
that of Quartz. Its peculiarity at first sight has been suf- 
* We have independent crystals of Quartz from Matlock, &c. of the same 
form. 
