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1. electrical properties

1. a symmetrical set of planes in space, associated with a crystal, having the same symmetry as the crystal class

2. magnetic properties

2. the act of splitting or the tendency to split along definite planes so as to yield smooth surfaces

3. crystal form

3. the energy of the exterior face of an object

4. fracture

4. anything detected by the sense of smell, odour

5. state of aggregation

5. the change in direction of a propagating wave, such as light or sound, in passing from one medium to another in which it has a different velocity

6. cleavage

6. the quality or condition of being hard

7. hardness

7. a quality, attribute, or distinctive feature concerned with a magnet

8. specific gravity

8. the splitting of a ray of unpolarized light into two unequally refracted rays polarized in mutually perpendicular planes

9. surface energy

9. a property of certain crystals of absorbing light to an extent that depends on the orientation of the electric vector of the light with respect to the optic axes of the crystal

10. taste

10. reduction of the intensity of radiation as a result of absorption or scattering by matter

11. smell

11. an attribute of things that results from the light they reflect, transmit, or emit in so far as this light causes a visual sensation that depends on its wavelengths

12. lustre

12. a quality, attribute or distinctive feature concerned with electricity

13. colour

13. the way in which a mineral or rock naturally breaks

14. refraction

14. the sensation experienced by means of the taste buds

15. double refraction

15. formed of separate units collected into a whole

16. extinction

16. the ratio of the density of a substance to that of water

17. pleochroism

17. the way in which light is reflected from the surface of a mineral

mean

to intend to convey or express

stand for

to represent or mean

signify

to indicate, show, or suggest

denote

to be a sign, symbol, or symptom of; indicate or designate

indicate

to be or give a sign or symptom of; imply

suggest

to evoke (a person, thing, etc.) in the mind of someone by the association of ideas