Plagioclase feldspar is a non-metallic mineral. It has 2 cleavages at nearly right angles. It is also differentiated from potassium feldspar because it contains striations. Potassium feldspar has 2 cleavages at nearly right angles.
Feldspar's fracture is brittle
cleavage lines
Cleavage .
cube
feldspar
Feldspar.
Orthoclase Feldspar.
2 at 90 degreesHere is a discussion on feldspar.It says it has uneven fracture and cleavage in 2 directions.http://www.theimage.com/mineral/feldspar/index.htm
Plagioclase feldspar is a non-metallic mineral. It has 2 cleavages at nearly right angles. It is also differentiated from potassium feldspar because it contains striations. Potassium feldspar has 2 cleavages at nearly right angles.
Cleavage and Fracture
Calcite can be identified by its rhombohedral cleavage and effervescence in acid. Feldspar can be identified by its two cleavage planes at nearly 90 degrees, and it often has a white to pink color. Both minerals can also be identified by their hardness using the Mohs scale.
Cleavage is a minerals ability to break into even pieces useful for identification. Cleavage in two directions equals Feldspar for example.
Step-like cleavage is a property of the mineral mica. Mica minerals exhibit a planar arrangement of atoms that allow them to easily separate along flat surfaces, giving them a distinctive step-like appearance when broken or cleaved.
Feldspar minerals typically exhibit two directions of cleavage at nearly 90 degrees to each other. This cleavage produces flat surfaces that intersect at right angles.
Orthoclase feldspar typically exhibits two cleavage planes at right angles to each other, forming blocky or prismatic shapes. Plagioclase feldspar, on the other hand, shows two cleavages at nearly 90 degrees but often also has a third cleavage at a slightly different angle, resulting in more varied forms.
Feldspar typically displays two cleavage planes at nearly right angles, forming a rectangular shape, due to its two prominent cleavage directions. In contrast, mica exhibits a single perfect cleavage plane which allows the mineral to be easily split into thin, flexible sheets.