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XIV.—Chapters on the Mineralogy of Scotland. Chapter Third.—The Garnets. 
By Professor HEDDLE. 
(Read 7th January 1878.) 
Abundant as are the localities in which garnet is found in Scotland, there 
are but few which yield specimens such as can be analysed. 
This is on account of an intermixture of quartz—for the most part in a 
eranular form—the granules being promiscuously scattered throughout the mass 
of the crystals. In three localities the intermixture 
is not promiscuous, but has been governed by some 
intermittent crystalline action. These localities are 
Glen Skiag in Ross, where, around a central nucleus 
of leucitoidal crystals of garnet, translucent quartz is 
arranged in layers which alternate with those of the 
garnet, conformably to the figure of its crystal. 
The two other localities are the first and third 
granitic veins to the east of Portsoy ; in both of which 
garnet of a pale brown colour is laced with quartz, 
which is arranged in a graphic manner, as in the felspar from an adjacent 
vein. At no other locality do I know of such an occurrence. The appearance 
of a section of a rhombic dodecahedron is somewhat like the figure. 

Lime and Alumina Garnet. 
(Ca)? Si? + Al? Si. 
Colourless Garnet; Water Garnet. 
This very rare garnet I found in small quantity in one of the old limestone 
quarries in the wood on Craig Mohr, opposite to Balmoral. 
It was in small, perfectly colourless, dodecahedral crystals, which were 
associated with grossular. 
Qualitative trials showed the absence of iron in either state of oxidation. 
Lime—Alumina, [ron Garnet. 
(Ca*)? Si? + (Al, Fe,)’Si? . 
Grossular. 
1. This also very rare garnet was associated with the former; it was 
imbedded in limestone along with idocrase and rarely epidote. 
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