HOVEY, THE FOYER METEORITES 13 
most abundant have been arranged by Dr. O. C. Farrington’ in the 
following order of importance: 
1. Iron 3. Silicon 5. Nickle 7. Calcium 
2. Oxygen 4. Magnesium 6. Sulphur 8. Aluminum 
The other elements of particular importance in this connection are 
carbon, chlorine, chromium, cobalt, copper, hydrogen, manganese, 
nitrogen, phosphorus, potassium and sodium. 
Mineral Constituents. 
Seven elements have been found in meteorites in the elemental or 
uncombined state. They are iron, nickel, cobalt and copper in the form 
of alloys, carbon, hydrogen and nitrogen. With these exceptions, the 
constituents of meteorites are chemical compounds and all but six of 
the whole list have their exact equivalents in minerals which are found 
in the crust of the earth. 
According to most authorities the constituents of meteorites may be 
divided into essential and accessory components as follows’: 
Essential. Accessory. 
Nickel-iron *Schreibersite 
Olivine (chrysolite) Diamond 
Pyroxenes (Orthorhombic) Graphite (Cliftonite) 
Pyroxenes (Monoclinic) Hydro-carbons. 
Feldspar (Plagioclase) Cohenite 
*Maskelynite. *\Toissanite 
*Troilite 
Pyrrhotite 
*Daubréelite 
*OIdhamite 
Tridymite 
Chromite 
Magnetite 
Osbornite 
Lawrencite 
Glass 
1 Journal of Geology. Vol. IX, p. 394. 1901. 
2&.Cohen. Meteoritenkunde I, p.322. 1894. The asterisk indicates the min- 
erals which are peculiar to meteorites and are not known to occur in the earth’s crust. 
