THE SCHUNDLER COMPANY


BASIC VERMICULITE INFORMATION AND DATA

(Click here for our current MSDS on Vermiculite)

(Click here for our MSDS on Ultra Mix and Ultra Mix II)



Confusion and Publicity about Vermiculite and Asbestos


There has been a lot of publicity during the last year or two about vermiculite and asbestos, and a lot of confusion as a result. Briefly stated, the problem goes back to a very real problem at what had been one of the largest vermiculite mines in America which was closed in 1990.

Commercially available vermiculites today are virtually free of any asbestos (like our South African vermiculite), or they contain only insignificant amounts similar to other products that are naturally occuring, mined, processed, and used throughout the industrial world today. To read more about this subject, click on any one of the following pages:



Origins and Characteristics....

Vermiculite is a member of the phyllosilicate group of minerals, resembling mica in appearance. It is found in various parts of the world, but currently the major mines are located in South Africa, China, Brazil, Zimbabwe, and the United States. The largest mine today is located in the Palabora region of North-Eastern Transvaal in South Africa. It's vermiculite is basically a hydrated phlogopite mica which has the remarkable ability to expand to many times its original volume when heated---a property known as exfoliation.


Pictures of Unexpanded and Expanded Vermiculite

Vermiculite: Unexpanded, Expanded and a Single Particle




 
TYPICAL CHEMICAL ANALYSIS
 
Element Percent by Weight
SiO2 38-46
AL2O3 10-16
MgO 16-35
CaO 1-5
K2O 1-6
Fe2O3 6-13
TiO2 1-3
H2 8-16
Other 0.2-1.2

 

Chemical Formula: (Mg,Ca,K,Fe11)3(Si,AL,Fe11)4O10(OH)2O4H2O
 



TYPICAL PHYSICAL PROPERTIES
TYPICAL PHYSICAL PROPERTIES OF EXFOLIATED VERMICULITE

Color:Light to dark brown
Shape:Accordion-shaped granule
Bulk density (a):64-160 kg/cu m
4-10 lb/cu ft
Moisture loss@110 °C (230 °F):4-10%
pH (in water):6-9
Combustibility:Non-combustible
Sintering temperature:1150-1250 °C
2100-2280 °F
Fusion point:1200-1320 °C
2200-2400 °F
Cation exchange capacity (b):50-150 me/100g
Specific heat:0.84-1.08 kJ/kgK
0.20-0.26 kcal/kgK
0.20-0.26 Btu/lb F
Waterholding capacity (a):220-325% by wt
20-50% by vol


THERMAL CONDUCTIVITY AT DIFFERENT BULK DENSITIES

Bulk densitiesThermal conductivity values
kg/cu mlb/cu ftLambda W/mKBtu in/sq ft h °F
56-643.5-4.00.0580.40
80-965.0-6.00.0640.44
160-19210-120.0710.49


TYPICAL SIZES, DENSITIES, AND NAMES OF EXPANDED VERMICULITE*

SIZESDENSITIESGRADES OR SIZES
MMINN/AKG/M 3LB/FT 3U.S.SYSTEM
VA and SC Mines
ASTM GRADE
DESIGNATIONS
INTERNATIONAL
and South African
165/8DOWN56-723.5-4.5N/A0-PremiumPremium (6)
85/16DOWN64-854.0-5.011-LargeLarge (4)
45/32DOWN72-904.5-5.522-MediumMedium (3)
20.08DOWN75-1124.7-7.03 3-FineFine (2)
10.04DOWN80-1445.0-9.044-Superfine (if VA or SC) *
or
3-Fine (if South African) *
Super Fine (1)
0.50.02DOWN90-1605.6-10.054-Superfine Micron (0)


*Note: In the United States, the ASTM Grade Designationd for Vermiculite (as outlined in ASTM C-516) have problems in the descriptions of fine and superfine grades. The South African "Superfine (1)" is too coarse to conform with the ASTM Grade "4-Superfine". Both the South African Fine and Superfine Grades conform to the ASTM designation for "Fine Grade". And during the last few years the American grade 4-Superfine and a grade 5 seem to be getting smaller and smaller so as to be more and more like the South African Micron, or smaller. To be sure, it's not a perfect world!

NOTE:These sizes and values are given for general information purposes only. The Schundler Company does not necessarily produce all these grades, and uses grades which may not conform to these specifications at all times.

The Palabora Vermiculite Mine
The Palabora Vermiculite Mine


For more information about vermiculite, you might want to look at:

The Vermiculite Home Page

Our basic, more generic page about vermiculite.


Vermiculite Statistics and Information
(http://minerals.usgs.gov/minerals/pubs/commodity/vermiculite/index.html
(published by the United States Geological Survey)

or look through the rest of our website, or call or contact us at:

The Schundler Company 150 Whitman Avenue Edison, New Jersey 08817
(ph)732-287-2244 (fax) 732-287-4185
www.schundler.com
email: info@schundler.com

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