Cristobalite

  • Sand
  • Silicon dioxide
  • Metacristobalite
  • Silicon(IV) oxide
  • quartz glass
  • Fuming silica
Formula
SiO2
Description
Glassy mineral - Vitreous form of quartz fount in Mexico. Glue gray, brown gran, yellow and white colors may be observed.
Uses
Part of a mineral/rock collector’s collection.

Registry Numbers and Inventories.
CAS
14464-46-1
EC (EINECS/ELINCS)
238-455-4
RTECS
VV7325000
RTECS class
Tumorigen; Human Data
Beilstein/Gmelin
9357 (G)
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
O2Si
Formula mass
60.09
Melting point, °C
1710
Boiling point, °C
2590
Density
2.27 g/cm3
Solubility in water
Insoluble
Surface tension
20 - 45 erg/cm3
Refractive index
1.48 - 1.51
Thermal expansion
5.366E-5/K3.58

Hazards and Protection.
Storage
Keep tightly closed. Store in a cool dry place.
Protection
Compatible chemical-resistant gloves. Chemical safety goggles.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, observing precautions in the Protective Equipment section. Avoid generating dusty conditions Provide ventilation.
Stability
Stable at normal temperature and pressure.
Incompatibilities
Incompatible with fluorine, oxygen difluoride, chlorotrifluoride, vinyl acetate.
Decomposition
Nature of decomposition products not known.

Fire.
Fire fighting
Extinguish using Water spray. Carbon dioxide, dry chemical powder, or appropriate foam. Wear self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes.
Hazards
Emits toxic fumes under fire conditions.

Health.
Exposure limit(s)
0.05 mg/m3 (respirable dust fraction) - ACGIH
Carcinogin
G-A2H, I-1, N-1, CP65
Exposure effects
   Ingestion
May cause irritation of the digestive tract.
   Inhalation
May cause allergic respiratory tract irritation. Inhalation of dust may cause respiratory tract irritation.
   Skin
May cause skin irritation. May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material.
   Eyes
Dust may cause mechanical irritation. Dusts may cause persistent eye irritation and conjunctivitis. Prolonged exposure to respirable crystalline quartz may cause delayed lung injury/fibrosis (silicosis).

First aid
 
   Ingestion
If victim is conscious and alert, give 2-4 cupfuls of milk or water Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing give artificial respiration. If breathing is difficult, give oxygen Get medical aid.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
   Eyes
Flush eyes with plenty of water for at least 15 minutes occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.