Vermiculite Properties

CHEMICAL FORMULA

(Mg,Ca,K,Fe11)3 (Si,AL,Fe111)4O10(OH)2O4H2O

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
H2O	8-16
Other	0.2-1.2

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
MOH Hardness:	1-2
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

Notes:

(a) Bulk density and water holding capacity vary with article size.
(b) Exchangeable ions are Mg+2 and Ca+2, sodium acetate saturation / ammonium acetate substitution method.

THERMAL CONDUCTIVITY AT DIFFERENT BULK DENSITIES

Bulk densities		Thermal conductivity values
kg/cu m	lb/cu ft	Lambda W/mK	Btu in/sq ft h °F
56-64	3.5-4.0	0.058	0.40
80-96	5.0-6.0	0.064	0.44
160-192	10-12	0.071	0.49

EXFOLIATED VERMICULITE PARTICLE SIZES

Size			Densities		Equivalent names/designations
mm	in		kg/cu m	lb/cu ft	System A	System B
16	5/8	down	56-72	3.5-4.5	NA	Premium (6)
8	5/16	down	64-85	4.0-5.0	1	Large (4)
4	5/32	down	72-90	4.5-5.5	2	Medium (3)
2	0.08	down	75-112	4.7-7.0	3	Fine (2)
1	0.04	down	80-144	5.0-9.0	4	Superfine (1)
0.5	0.02	down	90-160	5.6-10.0	5	Micron (0)

SAFETY, STORAGE AND HANDLING
Information on safe handling, storage, personal protection, health, and environmental considerations has been gathered on this product and is available from the material suppliers upon request. It is recommended that all users and specifiers acquaint themselves with this information.

We hope the information given here will be helpful. It is based on data and knowledge considered to be true and accurate and is offered for the user's consideration, investigation and verification but we do not warrant the results to be obtained. No statement, recommendation or suggestion is intended for any use which would infringe any patent or copyright.

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