Wednesday 13 August 2014

Silicate Structure

Nesosilicates  (Island Silicates)  
Oxygens atoms are not shared with other SiO4-4 tetrahedrons. Ratio between Si & O is 1:4. The basic structural unit is SiO4-4. Eg. Olivine and Garnet group (Mg,Fe)2SiO4.
The atomic structure of nesosilicates are generally dense which cause the mineral of this group to have high specific gravity and hardness. Crystal system is generally equidimensional and have poor cleavage.

Interview question



Commonly Asked (& Tricky) Interview Questions
Be Prepared for these!!!

v        Tell me about yourself.
v        What are your greatest strengths?  
v        What is your greatest weakness?                     

Pumices and Scoria

                                     
Pumice /ˈpʌmɨs/, called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough textured volcanic glass, which may or may not contain crystals. It is typically light colored. Scoria is another vesicular volcanic rock that differs from pumice in having larger vesicles and thicker vesicle walls and being dark colored and denser.