Final answer:
Silicate minerals can feature structures like independent tetrahedra, single and double chains, and sheets. These patterns affect the silica-to-oxygen ratio and the physical characteristics of minerals such as olivine, pyroxene, amphibole, and mica.
Step-by-step explanation:
The silicate structure of the major minerals includes independent tetrahedra, single chains, double chains, and sheets. In independent tetrahedra, each silica tetrahedron is a discrete unit and does not share any oxygen atoms with others, resulting in a mineral like olivine. In single chains, each tetrahedron shares two of its oxygen atoms forming a chain-like structure, which is exemplified by the mineral pyroxene. When these chains are doubled, with tetrahedra in one chain sharing oxygen atoms with those in a parallel chain, minerals like amphibole are formed. Lastly, sheet silicates, such as mica, occur when each tetrahedron shares three of its oxygen atoms to form two-dimensional sheets.