Part III. Of Gems. 285 
An AMETHYSTINE ROCK. The Gemlmh its Name 
from the opinion of its being an Amulet againft Drunken- 
nefs. This Rock confifteth of angular pointed and contigu- 
ous Cryftals ^ growing from both fides the Matrix, in- 
wards, where their Points meet,and are all clofely indented. 
Some of them feem to be Pentagonal. Several are Conic k 
from the Points towards the Roots. Thefe are well 
tinctur d, but the Roots are all white, or rather Diaphanous 
and colourlefs. As alfo is the Matrix, or inward part of it 5 
yet not fo clear. The (hell over all, flat, opacous, and of a 
redifh brown. There is the Figure of a very fair one 111 
Calceolarias Muf. 
ANOTHER,growing upon a Matrix or Bed fpotted red 
and yellow, and crofs-grain d , or compofed of (mall 
Cryftals fet together decujfatim. 
A THIRD, the Matrix whereof is a kind of Amethyftine 
Flint, i. e. not compofed of Cryftals or Grains, as is ufual, 
but one entire marly Stone, Semiperfpicuous, and of a pale 
blew, almoft of the colour of fome Cows Horns. Of an 
orbicular Figure, and fomewhat flat like a Loaf. The 
Roots of the Cryftals are colourlefs, as in the former, and 
the points and upper parts of a pale Purple. With thefe, is 
included in the fame Matrix, a whitifh and flaky Stone, 
which is eafily diffolved with Spirit of Nitre. Which is 
one, amongft many inftances , how near together two 
Stones may be bred, of fo different a nature one from 
another. 
A WHITE AMETHYST. This is here naked, or with- 
out a Matrix. Confifteth of divers contiguous Cryftals, 
half an inch and an inch long $ their Roots grey $ but 
their Points clear, ufually fexangular. From the Points the 
Roots taper d or conick : the Figure which doth efpecially 
diftinguiih this Stone from Cryftal, whether white, or of an 
Amethyftine colour. 
An AMETHYST of a pale Violet colour $ found grow- 
ing in Scotland. Given by Sir Rob. Moray. 
ANOTHER, with a kind of Chrysolite growing to it. 
The beft of this kind, are, as Theophraftm well defcribes 
them, of the colour of a ripe (red) Grape : and are the 
hardeft. Thefe grow in the Indies : the reft in Bohemia^ (a) Boet. <k 
Saxony, tec. The beft, being burnt, excellently imitate a & 
Diamond, (a) . Two 
