KINDS OF ROCKS. 453 



ish-wbite, tough rock, consisting of an alumina-lime garnet. 

 G. =3-39-3-49. From St. Francis, Canada. The superior 

 yellow novaculite or whetstone, of Vieil Salm, Belgium, has 

 the constitution, according to A. Eenard, of a manganesian 

 garnet. Metamorphic. 



3. Eclogyte. — Compact and tough. Consists of granular 

 garnet and hornblende, with grass-green smaragdite. G. = 

 3*2-3-5. A related rock consists of reddish or brownish- 

 } T ellow garnet, and black or greenish -black hornblende, with 

 often some magnetite. Metamorphic. 



4. Epidosyte. — Pale green to pistachio-green. Consists of 

 epidote mixed with quartz. Metamorphic. 



5. Eulysyte. — Fine-granular, consisting of chrysolite with 

 a diallage-like mineral and garnet. Forms a bed in gneiss 

 near Tunaberg, Sweden. 



6. Chrysolyte, or Chrysolite-Keck. — Yellowish to pale olive- 

 green, granular ; consisting almost wholly of chrysolite. 

 G. =3-3-1 ; H. =5-5-6. Abundant in Macon County, K 

 Carolina ; in part changed to serpentine. Metamorphic. 



Dunyte is yellowish-green ; granular, and consists of chrysolite, with 

 some chromite. From Mount Dun, New Zealand. Eruptive. 



7. Lherzolyte. — Greenish-gray ; crystalline granular. Con- 

 sists of chrysolite, enstatite, whitish pyroxene, with chrome- 

 spinel and sometimes garnet. From Lake Lherz, etc. Is 

 it metamorphic ? 



8. Picryte. — Blackish-green to brownish-red ; crystalline- 

 granular. Consists of chrysolite, with augite sometimes in 

 crystals. Graduates into chrysolitic doleryte. 



9. Limburgyte. — A semi-glassy rock, consisting of chryso- 

 lite and augite, with some magnetite. It is occasionally 

 amygdaloidal. Affords on analysis 43 per cent, of silica. 



8. HYDROUS MAGNESIAN AND ALUMINOUS ROCKS. 



Contain one or more of the hydrous magnesian minerals, 

 chlorite, talc, serpentine, or the related hydrous aluminous 

 mineral, pyrophyllite. The fine-grained kinds are more or 

 less greasy to the touch ; and some of them resemble the 

 hydromica slates. 



1. Chlorite Schist— Schistose ; color dark green to grayish- 

 green and greenish-black ; but little, if any, greasy to the 

 touch. Consists of chlorite, with usually some quartz and 



