256 ANNUAL OF SCIENTIFIC DISCOVERY. 



veals the fact, that, in the primitive beds, gold forms small veins, with 

 a quartzose gangue. 



The schistose fragments which exist in the valley of the Sacramen- 

 to give reason to think that the mountains which contain auriferous 

 veins consist rather of micaceous schist than of granite properly so 

 called. This conclusion agrees with the examination of washed au- 

 riferous sands. 



The general tint of the auriferous sands is black. We perceive at 

 first sight that the oxidulous iron predominates, and that it is that 

 mineral which causes the color. The analysis was therefore com- 

 menced by separating this by means of the magnet ; 3 grams gave 

 1.79, or 59.82 per cent. Notwithstanding the separation of this large 

 quantity of oxidulous iron, the sands still retained" their dark color ; 

 they were very rich in gold, and numerous spangles were more dis- 

 tinctly remarked. Examined by the microscope, the sands remaining, 

 after separation of the iron, contained some octahedrous crystals, some 

 with mirror-like facets and but little altered, others rounded, but still 

 brilliant. These crystals, by their form and the color of their dust, 

 appear to belong to titaniferous oxide of iron, and are mixed with flat- 

 tened crystals, whose hexahedrons projection and red dust cause them 

 to be considered as oligist iron. Lastly, among the black grains 

 were observed dull, irregular, and soft fragments, which have all the 

 character of manganese. Mixed with the titaniferous oxidulous iron, 

 in the second portion of the sands, were many crystals of white zir- 

 con, terminal at their two extremities. These crystals are for the 

 most part short. Their perfect transparency and absence of color 

 cause them at first to be taken for quartz, but where their facets are 

 counted, there can be no longer doubt that they belong to a prism hav- 

 ing a square base. Notwithstanding the smallness of these crystals, 

 their perfection is such, that the incidence of many of then* faces can 

 be measured. 



GOLD DUST FROM CALIFORNIA. 



FROM nearly all the deposits of gold which exist in various parts of 

 the world, the metal is obtained in part in the form of dust, or minute 

 grains disseminated through the sand, almost invisible to the eye. As 

 yet no returns of gold in this state have been received from California, 

 For the purpose of determining whether it really existed and had been 

 overlooked, a careful examination of several portions of the black 

 metallic residue left after washing in California has been made by Dr. 

 Hayes of Boston. The result shows that gold dust in large quanti- 

 ties exists mingled with the ferruginous and chromiferous sands, which 

 heretofore have been thrown away as worthless. Dr. Hayes estimates 

 the amount of gold in one ton of sand to be at least $1200. 



GOLD IN MARYLAND. 



A FEW months since, gold was discovered on the farm of Samuel 

 Elliott, in Montgomery County, Md. From the specimens already 



