84 Mr. J. Bryce's List of the Simple Minerals 



that rock at Benbradagh near Dungiven : one mass 70 pounds in weight, 

 and apparently a fragment of a crystal, was found there. It is found 

 also in the Granite of Down, and Mica Slate of Derry. 



Smoky Quartz. — In the Mourne Granite, and the Trachytic Porphyry of 

 Sandy Brae, Antrim. 



Amethyst. — Found in the Granite of Mourne, by Mr. Patrick Doran, in 

 small but beautiful crystals. 



Flint. — In the Chalk of Derry and Antrim. 



Common Opal. — Very common in the Trap rocks ; also in dykes of 

 Greenstone, traversing grauwacke in Down. 



Semi-opal. — Rare : in the Trap of Antrim. 



Precious Opal. — In the Porphyry of Sandy Brae, of a red and green co- 

 lour. Sir C. Giesecke. 



Calcedony. — Very common in Trap. 



Carnelian. — On the shores of Lough Neagh, where, according to Sir C. 

 Giesecke, Chalcedony, Sardonyx, Onyx, and Agates, also occur. 



Hyalite. — Occurs in glass-white botryoidal masses on the Granite of 

 Mourne. Sir C. Giesecke gives the Causeway as a locality. 



Heliotrope. — On the shores of Lough Neagh. 



Iron Flint. — In Rathlin, and according to Sir C. Giesecke on the shores 

 near the Causeway. 



Jasper. — In many parts of the Trap district, with the Coal of Coal Island, 

 and in Bowlders at Hollywood, Down. 



Splintery Hornstone. — In Bowlders, Ballymena ; Giesecke. Also in Green- 

 stone, Carnmoney, near Belfast. 



Conchoidal Hornstone. — In Bowlders, Rostrover ; Giesecke. 



Woodstone. — At Lough Neagh, and in the Alluvial Soil in the vicinity. 

 Also rarely in Down. 



Pitchstone. — Forms veins in Granite near Newry, and occurs in the Por- 

 phyry of Sandy Brae. 



Lydian Stone. — At Rostrover, Down ; Giesecke. Also in Trap at Magilli- 

 gan, Derry. 



Flinty Slate. — Abundant in Down. 



Pearl Stone. — Abimdant in the Porphyry of Sandy Brae. Also in Green- 

 stone near that place ; Giesecke. 



Common Felspar. — Very common. 



Glassy Felspar. — In masses, often very large, in the Trap rocks ; in small 

 bits in the Sandy Brae. 



Porphyry. 



Adularia. — In small decomposed fragments, Mourne; Giesecke. Mr. 

 Doran finds it there in the same rock in large opalescent masses. 



Labradorite. — Found by Mr. Doran in Mourne, of a dull gray colour, and 

 faint play of colours; it occurs in the Porphyry subordinate to Granite. 



Disintegrated Felspar. — In the Mourne Granite. 



Albite. — In the Mourne Granite, in small prismatic crystals. 



Apophyllite. — Crystallized in prisms variously bevelled, of splendent lustre, 

 from Dunseverie, near Giants' Causeway. 



Mornite. — Found in the Greenstone of Mourne, by Mr. P. Doran, and ana- 

 lysed and named by Dr. Thomson. It occurs in greenish-red masses, 

 and consists of silica, alumina, and lime. 



Chlorphcerite. — I found this substance lately in the Greenstone of Carn- 

 money near Belfast. It occurs massive; colour dark-green; lustre 

 vitreous. It is accompanied by specular iron, and is much more beau- 

 tiful than the Chlorphserites of England or Scotland. 



Common Hornblende. — Very common ; crystallized in acicular prisms : Fair- 

 head. 



