484 MINERALS. 



Bog ore is usually found in low, marshy places, as a result of the decomposition of other ores of iron, and 

 often incrusts plants, wood, &c. Limonite is one of the most widely diffused species of iron in the United 

 States, and yields a large quantity of the metal. It is however principally used for castings, since it is cold 

 short, as the term is, and cannot be used for wire, or where toughness is required. It is found in Vermont 

 at Colchester, Milton, Bristol, Huntington, Ripton, Starksboro, Warren, Wallingford, Highgate, Swanton, 

 Guilford, Bennington, Dorset, Manchester, Pittsford, Brandon, Chittenden and StrafFord. It can be seen 

 in the State Cabinet under Nos. 102 to 122 inclusive. 



Pyrolusite, or the Anhydrous Binoxyd of Manganese, with sometime a trace of silica and baryta, is a 

 common ore of manganese. In primary form it is a right rhombic prism. Its color is bluish-black, though" 

 in some instances, as at Chittenden, it occurs in brilliant steel-gray crystals. It is often found in connec- 

 tion with the other ores of manganese. In Vermont it occurs at Chittenden, Bennington, Brandon, Iras- 

 burgh and Monkton. It may be seen in the State collection from Nos. 79 to 90. 



Malachite, or Green Carbonate of Copper, is composed of protoxyd of copper, carbonic acid and water. 

 It is seldom found in a crystalline condition, but generally in fibrous botryoidal or stalactitic masses. Its 

 primary form, however, is referable to the oblique rhombic prism, and this often in twin crystals. It is 

 of a beautiful green color, and when in large masses and sufficiently compact, it is made into table tops, 

 vases, and even ornamental jewelry. Such specimens are found in Siberian Russia and Western Africa. 

 It usually accompanies the other ores of copper, and is considered as originating from them by the 

 action of atmospheric air and water. It is not found in large masses in Vermont, but occurs at Vershire in 

 well characterized specimens. It may be seen in the State Collection, No. 370. 



Albite. This mineral, formerly called Cleavelandite, is a silicate of alumina and soda, the latter of which 

 is sometimes partly replaced with potassa, or lime. It is often called a soda feldspar, to distinguish it from 

 orthoclase and Labrador! te. Primary form, oblique rhomboidal prism. In color it is pure white, which 

 characteristic is one of the most important physical signs for distinguishing this mineral. It occurs in 

 Cabot and Westmore, and may be seen in the Collection at the State House under Nos. 268, 269 and 270. 



Graphite, Plumbago, or Black Lead, is a carburet of iron. It is nearly all carbon, though there is 

 sometimes in it ten per cent, of iron. Other impurities are occasionally found mixed with the carbon. In 

 crystalline form it belongs to the Hexagonal System. It is usually found either fibrous or in six-sided flat 

 plates, with a steel-gray color and a greasy feel, and a black and shining streak. One of the best 

 localities in the world is at Borrowdale, England, and another is Ceylon. It is used for making fire 

 pots, lead pencils, and diminishing friction in heavy bearings. It occurs in Vermont at Brandon, Newbury, 

 Swanton Falls, Pittsford, Norwich, Hancock and Huntington. In the Cabinet it may be found under 

 No. 7. 



Staurotide. This mineral receives its name from the Greek word signifying a cross, since one variety of 

 its twin state is a cross. Its crystalline form is a right rhombic prism, and its chemical composition 

 silicate of alumina, iron, and magnesia. In color it is red or reddish-brown, and it has a white streak. It 

 has been found in Vermont at Cabot, Saxton's River, and is in the State Cabinet under Nos. 282 and 282^. 



Adamsite. This is regarded as a new Natural History species by Prof. C. U. Shepard. The following 

 is his letter upon it : 



" The mineral from Derby, Vt. is the substance which you had ticketed Gigantolite with a query. Its 

 mode of occurrence in thickly disseminated crystals, through mica slate, and its brittleness, would very 

 naturally suggest such an opinion. Its clove-brown color reminded me of Phlogopite. It has the feature 

 of remaining wholly unaltered, even in the most weathered specimens, which assimilates it to Margarite 

 and the Clintonite. Its crystalline form however is that of mica, and but for its perfect inelasticity and 

 greater hardness, it might coalesce with this species. Under these circumstances it appears to constitute a 

 new Natural History species', which with your approbation I should be pleased to call Adamsite, after our 

 lamented associate Prof. 0. B. Adams, who was also the first State Geologist of Vermont. For the 

 present I must content myself with a very brief description of the species. The crystals are quite uniform 

 in size, about one quarter of an inch in their longest diameter, by less than one twentieth of an inch in height, 

 Form, oblique rhombic prism of 120. Terminal planes smooth and shining; lateral planes very imperfect 



