Particles that form a sedimentary rock by accumulating are called sediment. Before being deposited, sediment was formed by weathering and erosion in a source area, and then transported to the place of deposition by water, wind, ice, mass movement or glaciers which are called agents of denudation.
A cuboid is a box-shaped solid object. It has six flat sides and all angles are right angles. And all of its faces are rectangles.
The overall shape is that of a tetrahedron (i.e., a pyramid with all faces being equilateral, or nearly equilateral, triangles). The carbon atoms uses sp3 orbitals to achieve this geometry. When all four attachments are different, the carbon is a stereocenter.