332 MR ANDERSON ON THE ANALYSIS OF CAPORCIANITE AND PHAKOLITE. 



consisted chiefly of silicate of lime, reproduced by the strong drying necessary for 

 the separation of the silicic acid, was then heated to redness with carbonate of 

 soda; and alumina and lime were precipitated respectively by ammonia and oxalate 

 ammonia. The precipitates thus obtained, weighed and subtracted from the first 

 weight, gave that of the pure silicic acid. The solution, after the filtration of the 

 silicic acid, was precipitated by caustic ammonia ; the precipitate, after being fil- 

 tered, washed, dried, and weighed, was dissolved in hydrochloric acid, and the 

 silicic acid left undissolved was weighed ; to the filtered solution potassa was 

 added in sufficient quantity to redissolve the alumina at first precipitated. By 

 this means iron and magnesia were left undissolved, which were again precipi- 

 tated from a solution in hydrochloric acid, the first by succinate, and the second 

 by phosphate, of soda. The weights of the silicic acid, peroxide of iron, and mag- 

 nesia, contained in the phosphate, being subtracted from the first weight of the 

 ammoniacal precipitate, gave that of the pure alumina. The solution filtered 

 from the ammoniacal precipitate was then treated with a solution of oxalate of 

 ammonia ; and the precipitate of oxalate of lime, after filtration and washing, was 

 heated to strong redness, and treated several times in succession with a solution 

 of carbonate of ammonia at a gentle heat as long as it continued to gain weight ; 

 and the lime was then weighed in the state of carbonate. The solution which 

 was left affer the separation of the oxalate of lime, was then evaporated to dry- 

 ness in a counterpoised platinum crucible, and the ammoniacal salts driven off 

 by a moderate heat ; after which a higher temperature was given for the purpose 

 of melting the remaining salts. These, which consisted of chloride of potas- 

 sium, chloride of sodium, and magnesia, were weighed together. By solution in 

 water the magnesia remained undissolved, and was filtered off, washed and 

 weighed ; to the solution, chloride of platinum and spirit were added, when the 

 double chloride of platinum and potassium fell, which was collected on a weighed 

 filter, and from which the quantity of chloride of potassium, and thence that 

 of the potassa, were determined. By subtraction of the weights of magnesia and 

 chloride of potassium from the first weight, that of the chloride of sodium was 

 obtained from which the soda was reckoned. 



CAPORCIANITE. 



This mineral was kindly presented to me for analysis by Professor BERZELIUS. 

 It was first observed by Dr PAOLO SAVI at Caporciani, in the valley of the Caecino. 

 where it occurs in a copper mine worked by two Englishmen of the names of 

 HALL and SLOANE, and has been described by its discoverer in his Memorie per 

 servire allo studio della costituzione fisica della Toscana, parte 2 da , 53. 



Caporcianite conducts itself before the blowpipe in a manner perfectly simi- 

 lar to the other zeolites, in so far as its fusibility and relation to the fluxes are 



