| Iddingsite is a mixture of orthopyroxene, maghemite, hematite, cristobalite, and amorphous silica that is formed from olivine. |
| Look up cristobalite in the textbook and describe a likely environment for the formation of this sample. |
| One potential use of common or potch opal is for the production of cristobalite for use as a dental and jewellery investment. |
| Analyses of some samples of the dense grey rimstone sinter showed weak reflections, indicating the possible presence of cristobalite. |
| Atoms of aluminum and sodium in the structure may help the stability of cristobalite as well. |
| The crystals, called cristobalite and tridymite, swim in clouds around stars just before they begin to form planets. |
