Scientific Intellir/cnce — Mincralojij and Chemistry. 183 



15. Calstron-baryte. — Sometime ago Dr Slieppard, Professor of 

 Chemistry in the Medical College of South Carolina, described as a 

 new species, a mineral he named Cahtron-bari/te. On analysis it 

 afforded sulphate of barytes 65.55, carbonate of strontia 22.30, car- 

 bonate of lime 12.15. Recent specimens of this mineral have been 

 carefully examined by the Professor, with results so various in re- 

 gard to the carbonates present, as to lead him to consider it a me- 

 chanical mixture of sulphate of barytes, strontianite, and carbonate of 

 lime, and, therefore, not entitled to be considered as a new mineral 

 species. The same appears to be the case with the Stromnite, a 

 mineral found near Stromness, in Oi-kney, analysed and named as a 

 distinct species by the di.scoverer, Dr Traill. 



16. Discovert/ of Euclasc in Connecticut, North America — This 

 rare and beautiful gem is found in a vein containing topaz and fluor- 

 spar. It occurs in yellowish white tabular crystals, which are thin 

 and transparent. The crystals sometimes occur lining cavities in silver 

 white mica, and occasionally imbedded in dark purple fluor-spar — 

 Silliman'g Amirican Journal, vol. xliii., p. 366. 



17. New locality of Geokronitc. — This mineral, of which we gave 

 Svanberg's analysis and description in the 33d vol. of this Journal, 

 p. 204, has been found at Meredo, in Gallicia. The variety resembles 

 the Swedish one, but has a greater specific gravity (= 6.43), and 

 contains neither Arsenic nor Zinc. According to Sauvage (Annalets 

 dcs Mines, xvii. p. 525), it i^ composed of lead, 64.89 ; copper 

 1.60; antimony, 16.00; and sulphur, 16.90. {Bcrzclius' Jahres- 

 Bericht, xxi. Jahrgancf, 'id Heft, p. 185.) 



18. Grcenoi'ite. — Under this name Dufrenoy (Annalcs ties Mines, 

 xvii. p. 529), has described a mineral from St Marcel, in Piedmont, 

 which he has thus dedicated to Mr Greenough of London. It is of 

 a dark rose-red colour ; is partly crystalline, partly crystallized ; has 

 three cleavages, of which the second is parallel to the lateral planes, 

 and forms, with the others, an angle of 11° 35'. The specific 

 gravity = 3.44. It scratches fluorspar, but not glass. It is not 

 afted on by acids, and is not fusible before the blowpipe. With 

 fluxes, however, it affords the reactions denoting titanium and man- 

 ganese. According to the analysis of Cacarrie, it consists of 74.5 

 titanic acid, and 21.8 oxide of manganese, with traces of lime. 

 (Bcrcelius' Jahres-Bericht, xxi. p. 180.) 



19. Blue Colour of l.apis Lariili. — Eisner has made some experi- 

 ments on the blue colour of the Lapis Lazuli, and has ascertained 

 that it is caused by a .silicate of ahiminii and soda, wliich may bo 

 replaced by lime, combined with a iloublo sulphuret ol' sodium and 

 iron, ill which (he amount of ir'in ih verv small. Init is essential f r 



