[234] This metal has subsequently (namely, in 1844) been found to constitute a percentage in the native copper of the Eagle River mines of Lake Superior. Traces of it were found in a mass of native copper found on the shores of Keweena Lake, by Mr. Moliday, in 1826. A mass of pure silver was discovered in a boulder in the drift of Lake Huron, west of White Rock, in 1824. These discoveries induce the belief that this element will be found to be extensively present in the eventual metallurgic operations of the Lake Superior basin. b. _Silicious Minerals._ 1. QUARTZ. This interesting species being distributed in its numerous varieties throughout the region visited, I shall confine my notices to a few localities. Subs. 1.--_Common Quartz._ Occurs in the form of large water-worn masses along the shores of Lakes Huron, Michigan, and Superior. Also, in veins in the granite of Lake Superior, and in the argillite of St. Louis River. These localities all consist of the opaque varieties, with a slight degree of translucence in some places. It exists in mass at Huron Bay, Lake Superior, and in fragments of red jasper on Sugar Island, St. Mary's River. 1. _Radiated Quartz._--In detached masses on the Grange, and also at the rapids of the River Desmoines, on the Upper Mississippi. At the Grange, the crystals, which are usually minute, sometimes possess a cinnamon color, or pass into a variety of crystallized ferruginous quartz. 2. _Tabular Quartz._--In small, flattened masses along the shores of Lake Pepin. These masses are transparent, or only translucent. Their color is generally white, but sometimes yellow. They appear to be closely allied to chalcedony. 3. _Greasy Quartz._--In detached masses along the shores of Lake Superior. 4. _Granular Quartz._--At the Falls of Puckaiguma, on the Upper Mississippi, in large, compact beds rising through the soil. Also, in some conditions of the cliffs commencing at the Falls of St. Anthony, Carrer's Cave, &c. 5. _Arenaceous Quartz._--This is sometimes the condition of fine, even-grained, translucent sand rock of the preceding localities. Valuable as an ingredient of glass. 6. _Pseudomorphous Quartz._--On the shores of Lake Pepin, occasionally. These masses appear to have taken their crystalline _impress_ from rhomboidal crystals of carbonate of lime. 7. _Amethystine Quartz._--In the trap-rock of Lake Superior. Subs. 2.--_Amethyst._