MINERALOGY. 459 



The water goes off only on strong ignition, when the powdered min- 

 eral from being white becomes brownisli black. 

 The empirical' formula calculated is: 



lU"2Al,Si,aO40 



EydronepheUte. — A zeolitic mineral derived from the alteration of 

 sodalite of Lit'jhfield, Maine; it is named and described by Clarke and 

 Diller. It is found in seams, yielding specimens 2 centimeters in thick- 

 ness. It is white, lusterless, with the fracture of sodalite. Optical ex- 

 amination made it probable that it belonged either to the tetragonal or 

 hexagonal system. The hardness is 4,5. An analysis yielded : 



100.27 



for which the formula nNa2Al3Si30i:.+3H20 is calculated. The formula 

 requires silica 39.29, alumina 33. 4l, soda 13.54, water 13.76. It is allied 

 in composition to thomsonite, but contains soda. 



Kainositc (or C^kosite). — Described by A. E. Nordenskiold as a new 

 yttrium mineral and named from the Greek [xacMj:;, unusual) in allusion 

 to its remarkable composition. The mineral is known thus far only 

 from a single fragment of a six sided prism from Igeltjern on Hittero. 

 It is said to belong to the orthorhombic or monoclinic system, and 

 shows two unequal cleavages at an angle of 90°. or nearly 90°. The 

 color is yellow-brown, the hardness 5.5, the specific gravity 3.413, the 

 fracture subconchoidal. The mean of two analyses gave: 



20 



:100.10 



The formula given is 2CaO. (¥.03, Er203). 4Si02. CO^. 2H2 J, requir- 

 ing SiOi 34.07. Yr^Oa 37.00 (at. wei-ht=200.3), CaO 10.18, CO^ 0.35. IT2O 

 5.20. The natural supposition that the carbon dioxide is due to ad- 

 mixed calcite is said to.be proved to be untrue bj' microscopic exami- 

 nation. 



Kaliojyhilite. — A mineral allied to nephelite described by Mierisch 

 as occurring in the masses ejected from Mt. Somma, together with au- 

 gite and melilite. It forms thick prisms or fine thread-like colorless 

 crystals, probably belonging to the hexagonal system. An optical ex- 

 amination showed the mineral to be uniaxial with negative double re- 

 fraction. The cleavage is basal, distinct; it is very brittle. The specific 

 gravity is 2.602. An analysis yielded : 



Si02 Al20a(Fe.A) CaO Kfi KajO 



37.44 32.43 2.18 27.20 2.2(5=101.51 



This corresponds to the formula KoAl^SioOg, which is analogous to that 

 of an anhydrous muscovite, and corresponds to nephelite, anorthite, 

 andeucryptite, which contain sodium, calcium, and lithium, resj)ectively, 



