Prof. T. G. Bonne!/ — Ligurian and Tuscan Serpentines. 367 



parallel to oo P are indicated by thin lines of serpentine. The same 

 change is common in other serpentine rocks which I have examined. 

 This second minex*al can be seen with a hand-lens, forming a talc- 

 like border to the unaltered crystal ; probably it is nearly allied to 

 that mineral. One small grain of picotite is present, and some of 

 the most minute opacite is dichroic, and is probably manganese. 

 Through the kindness of Prof. Liveing a specimen of this second 

 rock has been examined for me at the Cambridge University Labora- 

 tory by Mr. C. T. Heycock, of King's College, to whom I return my 

 best thanks. Together with his analysis I reprint for comparison 

 those of serpentines very similar in appearance from Ayrshire and 

 Cornwall. 



Levanto. 

 S. G. 2-705 

 HoO \ 



Fe.S J n " 61 



SiO, 4047 



AL0 3 4-35 



It :::: } ™ I 



CaO 0-84 



MgO 34-59 



MnO 15 



NiO 0-49 



Residue 



Balhamie. 1 



Cadgwith. 3 





S. G. 2-587. 



14-08 



12-35 



trace 



0-41 



38-29 



3850 



3-95 .... 



102 



2-53 



4-66 



4-04 



;.... 3-31 



0-57 



1-97 



35-55 



36-40 



trace 





0-15 



0-59 





1-37 



100-11 9916 10058 



All dried at 100° Cent. In the Levanto specimen there was the slightest trace of 

 C0 2 . Hydrochloric acid dissolved 95-54 per cent, of the mass, leaving 4 46 residue 

 as a slightly green amorphous powder. The per-centage of alumina here, as in the 

 Ayrshire specimen, is larger than I should have anticipated, as I cannot see a 

 trace of felspar. Part of it, however, may he due to the pyroxenic constituents, 

 and the rest to picotite. The constant presence of nickel is interesting. 



My next visit was to the quarries from which is obtained the 

 celebrated Verdi di Prato, for centuries one of the most important 

 decorative stones in the valley of the Lower Arno. These are at 

 Figline, a little village between two and three miles from Prato, a 

 town between Florence and Pistoia. Here also the serpentine, as 

 may be seen from the railway, occupies a considerable tract of hilly 

 country, and rises from beneath the calcareous strata which are so 

 common in this part of the Apennines. Figline lies on the last 

 slopes of the hills, and on approaching it from Prato the serpentine 

 (which has the usual dusty purplish-brown or greenish-brown colour 

 and characteristic weathering) is seen forming the right bank of 

 the valley ; while on the left bank is exposed an indurated argil- 

 laceous rock, disturbed and sharply jointed, its aspect suggesting, as 

 does the contour of the serpentine mass itself, that the latter rock 

 is intrusive. The quarries, which are rather numerous, are situated 

 on the hill-side behind Figline. Almost directly on quitting the 

 village at the lower end, we come upon coarse gabbro, of the usual 

 character, but very rotten, and after ascending perhaps a hundred 



1 Quart. Journ. Geol. Soc. vol. xxxiv. p. 771. 



2 Quart. Journ. Geol. Soc. vol. xxxiii. p. 925. 



