352 SYSTEMATIC DESCRIPTION OE PRECIOUS STONES 



schist in the Alp-Lolen in the Maigels-thal on the boundary between Cantons Uri and 

 Graubiindten (Grisons). The crystals vary in size, but none are much bigger than a pea ; 

 each usually encloses a gi'ain of quartz. At the present time they are scarcely sought for 

 at all. Beautiful druses of hessonite occur in crevices in serpentine (Plate XIV., Fig. 7)? on- 

 the Mussa-Alp, in the Ala valley in Piedmont. The crystals of hessonite are here 

 associated with crystals of dark green chlorite and of pale green diopside : a number of the 

 latter are represented among the garnets in the figure just quoted. These, as well as very 

 similar specimens from Achmatovsk, in the Urals, are beautiful objects, to be seen in all 

 mineral collections, and illustrate the natural occurrence of this stone in a very striking 

 manner. 



Hessonite is rarely cut en caboclion ; more usually it is cut with facets (Plate XIV. ^ 

 Fig. 8) in one or other of the forms mentioned above. The colour of this stone being pale 

 it is unnecessary to hollow it out at the back or to make it specially thin. Cut hessonites 

 are usually mounted upon a burnished foil, they are rarely set a jour. 



SPESSARTITE. 



The spessartite from Amelia Court House, Virginia, U.S.A., is very similar in colour to- 

 hessonite. It is a manganese-aluminium garnet, containing manganous oxide in place of 

 lime. At the locality mentioned it is found in the mica mines in the granite as beautiful, 

 clear crystals, which have yielded stones of very good quality weighing from 1 to 100 carats. 

 Spessartite from other localities is scarcely suitable for cutting as a gem. 



ALMANDINE. 



Almandine is the deep red variety of garnet to which the name carbuncle used to be 

 given. The name was applied to other red stones, but most frequently to garnet. It is 

 generally believed that the word almandine is derived from Pliny's name for the stone^ 

 which was carbunculus alabandicus, since, according to his statement, it was found near the 

 town of Alabanda, in Caria (Asia Minor), where also it was cut. At the present time 

 transparent specimens of this kind of stone are commonly referred to simply as precious 

 garnet. 



Almandine, as shown in the analysis quoted above, is an iron-aluminium garnet 

 containing, beside the predominating ferrous oxide and alumina, small quantities of ferric 

 oxide, manganous oxide, &c. 



The red of almandine is always dark in tint, but varies somewhat in different 

 specimens. The colour is no doubt due to the large amount of iron which enters into 

 the composition of the mineral. It is often distinctly tinged with violet, and is then 

 described as columbine-red (Plate XIV., Figs. 3 and 4; Plate XVIII., Fig. 7). Shades 

 of colour between brownish-red and reddish-brown are also not infrequently seen. The 

 brownish-red stones are sometimes known to jewellers as vermeille garnet (vermilion 

 garnet), or simply as "vermeille'''; but the term is somewhat loosely applied, and often 

 includes the Bohemian garnet or pyrope, which is deep red with a tinge of yellow. In 

 artificial light almandine loses but little of its beauty ; the colour, however, is then more 

 inclined to orange or hyacinth-red and approaches that of hessonite. When heated, 

 almandine becomes black, but returns to the original red colour when cooled, though the 

 fine appearance of the stone is somewhat impaired by this treatment. 



