Mineralogy and crystallography questions.

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#	Question
1	Give two examples of minerals in each of the following crytal habits and aggregates Dendritic Botryoidal Bladed Fibrous Short answers
2	Citing one example of minerals that show solid solution, show how the specific gravity of minerals is influenced by the atomic mass numbers of the constituent atoms. Short answers
3	Giving one example in each case, explain how ionically bonded minerals differ from their covalent bonded counterparts in terms of their respective crystal symmetries. Short answers
4	Name two gemstone minerals in each of the following group of minerals Oxides Nesosilicates Short answers
5	Explain why $SiO_{2}$ minerals including quartz and its polymorphs are classified as silicates and not oxides although they have similar chemical formula to oxides of the general formula $XO_{2}$ (Where X can be Ti, Mn, Sn, U or Th). Short answers
6	Give reasons why $Al^{3+}$ is able to substitute for $Si^{4+}$ in $SiO_{4}$ tetrahedra to form $(AlO_{4})^{5-}$ units. Short answers
7	What is the compositional difference that exists between Orthoclase $(KAlSi_{3}O_{8})$ and Leucite $(KAlSi_{2}O_{6})$ ? Short answers
8	Why are nesosilicate minerals able to form equidimensional crystals? Short answers
9	Most of the phyllosilicates are hydroxyl bearing minerals. Considering their structural arrangement , show by using a neat illustrated diagram, the location of the OH group in relation to the $SiO_4$ tetrahedra. Short answers
10	The thirty two crystal classes you learnt in crytallography are grouped into six crystal systems of minerals. List all the six crystal systems in order of their increasing symmetry and differentiate them on the basis of their crystallographic axes. Also , give two examples of minerals that belong to each of the crystal system. Long answers