MINERALOGY. 487 



Gen. 1. Corneous Silver. 2. Corneous Mercury. 



ORDER IV. MALACHITE. 



No metallic lustre. Colour blue, green, brown. No single distinct faces 

 of cleavage. Hardness = 2.0, 5.0. Sp. gr. 2.0, 4.6. If 

 brown in colour or in streak, the hardness = 3.0 and less, and the 

 sp. gr. above 2.5. If white in the streak, the sp. gr. 2.2 and 

 less, and the hardness under 3.0. 



Gen. 1. Copper green. 2. Liriconite. 3. Olivenite. 4. Blue Ma- 

 lachite, or blue Copper. 5. Emerald Malachite. 6. Green Mala- 

 chite. 7- Atacamite. 



ORDER V. MICA. 



Cleavage monotomous and very distinct. Hardness = 1.0, 4.5. 

 Sp. gr. 1.8, 5.6. If metallic lustre, the sp. gr. is under 



2.2. If no metallic lustre, the sp. gr. is above 2.2. If the streak 

 is yellow, the sp. gr. is under 3.2. If the hardness is above 2.5, 

 it is rhomboidal ; if the sp. gr. is under 2.5, it is metallic ; if 

 above 4.4, the streak is white or gray. 



Gen. 1. Copper Mica. 2. Uran-Mica, or Uranite. 3. Cobalt Mica, 

 or red Cobalt. 4. Antimony Mica, or White Antimony. 5. Blue 

 Iron, or Iron Mica. 6. Graphite. 7- Talc-Mica. 8. Pearl-Mica. 



ORDER VI.SPAR. 



No metallic lustre. Streak white or gray, and brown. Hardness 

 = 3.5, 7.0. Sp. gr. = 2.0, 3.7. If rhomboidal, the sp. gr. 

 = 2.2, and less, or the hardness 6.0. If hardness =. 4.0, the 

 cleavage is monotomous. If hardness above 6.0, the sp. gr. is un- 

 der 2.5, or above 2.8, and the lustre is pearly. If sp. gr. above 



3.3, the combination is hemi or tetarto-prismatic, or the hardness 

 = 6.0, and no adamantine lustre. If sp. gr. = 2.4, and less, there 

 are traces of form and cleavage. 



Gen. 1. Schiller-Spar. 2. Kyanite. 3. Spodumene. 4. Prehnite. 

 5. Datolite. 6. Zeolite. 7- Petalite. 8. Felspar. 9. Augite. 

 10. Azure spar. 



ORDER VII.GEM. 



No metallic lustre. Streak white or gray. Hardness = 5.5,- 

 10.0. Sp. gr. 1.9, 4.7. If hardness = 6.0, and less, the sp. 

 gr. = 2.4, and less, and no traces of form or cleavage. If sp. gr. 

 is less than 3.8, there is no pearly lustre. 



