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XXXIX. Short Reports from the Chemical Laboratory of Tri- 

 nity College, Dublin (Nos. 2 and 3). By J. Emerson- 

 Reynolds, M.D., M.R.I. A., Professor of Chemistry, Uni- 

 versity of Dublin* '. 



No. 2. — On Franklandite, a new Mineral Borate. 



MANY analyses have been made from time to time of 

 sodio-calcic borates, brought chiefly from the Peruvian 

 province of Tarapaca. Most of the analyses seem to show 

 that the specimens of borates examined were mixtures of some 

 predominant mineral, such as the well-defined Ulexite, with 

 varying quantities of one or more borates containing a larger 

 proportion of sodium than Ulexite. I have lately had the op- 

 portunity of examining a specimen of a borate from Tarapaca 

 which has the same components as Ulexite, namely sodium, 

 calcium, boron, oxygen, and water, but which is much richer 

 in alkali than that mineral, and which seems to be a nearly 

 pure specimen of the mineral with which I supposed Ulexite to 

 be often associated. The specimen I analyzed was brought 

 from Peru by Mr. Graves, and was kindly placed in my hands 

 for examination by the Rev. Dr. Haughton. 



The specimen consists of a felted mass of long, thin, inter- 

 laced fibres, which are white in colour and possess a silky 

 lustre. Under the microscope, the fibrous crystals taken from 

 the cleanest portions of the mass were seen to be free from any 

 but traces of granular coating, and presented the same general 

 aspect. 



The hardness is not greater than 1 ; and the specific gravity 

 proved to be 1*65. 



The mineral is easily fused, first losing much water. 



The taste of the mineral is first slightly saline, owing to the 

 presence of a little admixed common salt, and is afterwards 

 somewhat alkaline. It is slightly soluble in water, but is 

 easily and almost completely dissolved by dilute hydrochloric 

 and nitric acids, the minute residue consisting of particles of 

 clay. 



When portions of the mineral mass were digested with 

 nearly ice-cold water, a sensible quantity of chloride was 

 dissolved out. The solution, evaporated on a glass micro- 

 scopic slide, afforded the well-known crystals of sodic chlo- 

 ride. A little calcium was also dissolved by the water. In 

 some of my earlier experiments upon this body I was led, 

 through the carelessness of a junior assistant, to suppose that 

 the percentage of chloride present was much greater than it is 



* Communicated by the Author, having been read before the Royal 

 Irish Academy. 



