Question map
Which one of the following minerals is NOT a naturally occurring silicate ?
Explanation
Bauxite is not a naturally occurring silicate mineral; rather, it is a rock composed primarily of hydrated aluminium oxides [2]. It is the principal ore of aluminium and is described as a clay-like substance containing minerals such as gibbsite, boehmite, and diaspore [3]. In contrast, Feldspar is a framework silicate (tectosilicate) and is the most abundant mineral group in the Earth's crust [2]. Zeolites are also framework silicates characterized by open structures with channels. Mica belongs to the phyllosilicate (sheet silicate) group, known for its distinct layers and perfect basal cleavage [2]. While bauxite forms through the decomposition of rocks rich in aluminium silicates under tropical weathering conditions, the resulting ore itself consists of oxides and hydroxides rather than silicates [4].
Sources
- [1] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 9: Distribution of World Natural Resources > Bauxite (aluminium) > p. 33
- [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 13: Types of Rocks & Rock Cycle > 13.5. Some Rock-Forming Minerals > p. 175
- [3] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 7: Resources > Natural Resources of India > p. 18
- [4] NCERT. (2022). Contemporary India II: Textbook in Geography for Class X (Revised ed.). NCERT. > Chapter 5: Print Culture and the Modern World > Bauxite Bauxite > p. 110