The vermiculite is one kind of laminated structure contains the magnesium the water aluminosilicate secondary metamorphic mineral, outside the undressed ore resembles the mica, usually by is black (gold) the mica becomes after the hydrothermal alteration function or the decency, when its being heated dehydration inflation assumes the winding shape, the shape resembles, therefore calls the vermiculite. The vermiculite is Mg x (H 2 O) {Mg 3 ~ x [ AlSiO 3 O 10 ] (OH) 2}. The vermiculite divides according to gradualness into the vermiculite undressed ore and the inflation vermiculite, may divide into the golden yellow vermiculite, the silver-white color vermiculite, the cream color vermiculite according to the color classification.
  The vermiculite has the heat insulation, bears, antibacterial, the fire protection, absoring water, the sound absorption frozen and so on the outstanding performance, in 800 ~ 1,000 ℃ under roasts 0.5 ~ 1.0 minutes, the volume may rapidly increase 8 ~ 15 times, most reaches as high as 30 times. After inflation proportion 50-200kg/m3, the color becomes golden yellow or the silver-white color, produces an idioplasm loose inflation vermiculite.
  The inflation vermiculite widely uses in to construct, department and so on metallurgy, chemical industry, light industry, machinery, electric power, petroleum, environmental protection and transportation, overseas mainly uses to construct, aspect and so on insulation, padding and agriculture, gardening.
First, mineral nature (1) physical property
  The vermiculite has the heat insulation, bears, antibacterial, the fire protection, absoring water, the sound absorption frozen and so on the outstanding performance, in 800 ~ 1,000 ℃ under roasts 0.5 ~ 1.0 minutes, the volume may rapidly increase 8 ~ 15 times, most reaches as high as 30 times. The color becomes golden yellow or the silver-white color, produces an idioplasm loose inflation vermiculite, but is not acidproof, it lies between the electricity characteristic to be also worse.

 

Outward appearance	Gloss	Color	Density g/cm 3	Degree of hardness	Loose Density kg/m 3	Melting point ℃	Compressive strength MPa	Refraction limit	Water content %
Scaled, laminated or the clinorhombic system false crystal, the lamella overlaps, may fold 1 million pieces in the 2.54cm thickness	The pearly luster oily luster non- gloss surface gloomily assumes the many kinds of gloss	Golden yellow brown brown green dark blue black and varicolored, 条痕 white	2.2 ~ 2.8	1 ~ 1.5	1,100 ~ 1,200	1,320 ~ 1,350	100 ~ 150	Ng=1.525 ~ 1.561 Np=1.545 ~ 1.581	7

 

  (1) relative humidity 100%, 24h.
When (2) -20 ℃, after 15 freezing and thawing, its size composition is invariable.
  (2) chemical composition
  The vermiculite is the chemical composition complex to contain water the aluminosilicate mineral, because its change does not decide, with the sole chemical formulation is difficult. Generally speaking, the vermiculite chemistry molecular formula is: (Mg, Ca) 0.7 (Mg, Fe 3+, Al) 6.0 [ (Al, Si) 8.0 O 20 ] (OH 4. H 2 O). Usually, SiO 237 ~ 42%, Al 2 O 39 ~ 17%, Fe 2 O 35 ~ 18%, MgO11 ~ 23%, H 2 O5 ~ 11%, Ca, Na, the K content does not decide. But because hydrated degree different, oxidation not one, even if with is a vermiculite, its chemical composition is also difficult to be same. World partial habitats vermiculite chemical composition

  Vermiculite main chemical composition

Ingredient	SiO2	Al2O3	MgO	Fe2O3	CaO	PH	H2O
Content (%)	37-42	9-17	11-23	5-18	0.5-0.8	8-11	<1

 

 

  Second, main use
  The fresh vermiculite after the high temperature roasting, its volume can rapidly inflate the several fold to dozens of times, after the inflation vermiculite average is 100 ~ 130kg/m 3, has between the tiny air the insulation, thus is one kind of fine heat preservation, the heat insulation, the sound absorption, bears the frozen eclipse building material, the industry padding, the coating and the fire-proof material. The inflation vermiculite widely uses in to construct, department and so on metallurgy, chemical industry, light industry, machinery, electric power, petroleum, environmental protection and transportation, overseas mainly uses to construct, aspect and so on insulation, padding and agriculture, gardening.