Types Of Twinning In Thin Section
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B when the prism angle is 70.
Types of twinning in thin section. Twinning is the symmetric intergrowth of two or more crystals of thesame mineral and commonly is revealed in thin section by the differentcrystals of the same mineral having different extinction positions or differentinterference colours. Home rocks and minerals quartz thin section reference url share. The twins may be wedge shaped thicker at one end if the twinning results from deformation.
Contact twins this occur if a definite composition plane is present. Growth twins when accidents occur during crystal growth and a new crystal is added to the face of an already existing crystal. May include indication of whether the.
Twins of this type are also common. In both the cases the twins are of penetration type. Twinning can originate in 3 different ways as growth twins transformation twins and glide or deformation twins.
This mineral shows cruciform twins of two types. Quartz thin section view description. B sea horse twin in which the face 231 is a twin plane.
Simple twins composed of only two parts. Seen only in triclinic feldspars. A right angled cross these result when face 031 is a twinning plane.
Small 250x250 max medium 500x500 max large. A few notes about twinning or other internal features of crystals may be given. Add tags comment rate.
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