114 THE TRIAS OR NEW RED SANDSTONE. 



are Amethyst and Transparent Quartz in six-sided pyramids, 

 Agate, Chalcedony, Carnelian, and Jasper. The best localities 

 for these minerals are Blomidon, Scott's Bay, Digby Neck, 

 and Partridge Island. A fine variety of Moss Agate occurs 

 at the Two Islands, and a sort of Quartz Sinter in imperfect 

 crystals and beautiful coralloidal forms in the neighbouring 

 promontory of M'Kay's Head. Large quantities of fine Agates 

 and Jaspers, applicable to ornamental purposes, may be found 

 at Cape Blomidon and Digby Neck ; and the Amethyst of the 

 same localities is sometimes in sufficiently large crystals to 

 admit of being cut for ring-stones, seals, etc. 



Opal — occurs at a few localities, in the plain variety of semi-opal ; 

 and very frequently, in the form of white chalky Cacholong, 

 forms the basis of fine crystallizations of amethyst, having 

 lined the cavities of the trap before the latter was deposited. 



Heulandite — Hydrous Silicate of Alumina and Lime, in fine rhombic 

 prisms, colourless and light flesh colour, at Blomidon, Black 

 Rock, Partridge Island, etc. Minute yellow crystals are found 

 at Two Islands. 



Stilbite — Hydrous Silicate of Alumina, Lime and Soda, or Potash, 

 in radiated and sheaf-like aggregations of crystals of honey- 

 yellow and brown colours, at Partridge Island, Sandy Cove, 

 Blomidon, Black Rock, etc. Fine groups of white crystals 

 are found at Black Rock in King's County and its vicinity. 



Mcsotype. — The variety or species Natrolite, the Hydrous Silicate of 

 Alumina and Soda, is found in small prismatic crystals and 

 in radiated masses of crystals, at Blomidon, Two Islands, 

 M'Kay's Head, Scott's Bay, etc. The variety Scolecite, or 

 Hydrous Silicate of Alumina and Lime, is found at the same 

 localities, also in radiating and prismatic forms. The variety 

 Mesolite, or lime and soda Mesotype, is also found at various 

 localities. 



Laumonite — Hydrous Silicate of Alumina and Lime, in whitish and 

 light red prismatic crystals, at Peter's Point, Black Rock, 

 Sandy Cove, etc. This mineral, very beautiful when freshly 

 taken from the rock, loses Avater and becomes opaque and 

 brittle when exposed to air and light. I have found that this 

 change takes place very rapidly when the specimens are 

 exposed to sunlight, and is much retarded by keeping them 

 in darkness. Immersion in gum- water is also a preventive. 



Chabazlte — Hydrous Silicate of Alumina, Lime, Soda, and Potash. 

 The flesh red, brownish red, purplish red, and yellowish red 



