General Vermiculite Information

Chemical Formula:

(Mg,Fe++,Al)3(Al,Si)4O*0(OH)2•4(H2O)

Composition:

Molecular Weight = **4.*9 gm

 Magnesium   8.*8 %  Mg   *4.*9 % MgO

 Aluminum   *3.*1 %  Al   *3.*8 % Al2O3

 Iron        9.*7 %  Fe   *2.*2 % FeO

 Silicon     5.*7 %  Si   *1.*2 % SiO2

 Hydrogen    2.*0 %  H    *7.*7 % H2O

 Oxygen     *0.*7 %  O

           ______        ______ 

           **0.*0 %      **0.*8 % = TOTAL OXIDE

Empirical Formula:

Mg1.8Fe2*0.9Al4.3SiO*0(OH)2•4(H2O)

Environment:

Appears to have been formed by weathering or hydrothermal alteration of iron-bearing phlogopite an annite.

IMA Status:

Valid Species (Pre-IMA) ***4

Locality:

Millbury, Worchaster County, MA, USA Link to MinDat.org Location Data.

Name Origin:

From the Latin vermiculus, "little worm."

Name Pronunciation:

Vermiculite + Pronunciation

Synonym:

Batavite - Fe-poor variety of vermiculite

Hydrobiotite

Hydromica

Jeffersinite