Naturally occurring square shapes are rare because nature tends to favor more irregular, rounded, or fractal-like patterns due to the processes and forces involved in growth and formation. However, there are a few examples where nature approximates square shapes:

1. Pyrite Crystals: Also known as fool’s gold, pyrite can form near-perfect cubic (square-shaped) crystals. These are formed through natural geological processes where the crystal growth favors a cubic system due to its molecular structure.
2. Salt Crystals: When salt (sodium chloride) crystallizes, it often forms cubic structures. These can be seen in salt flats where large, flat beds of salt are left behind after bodies of saltwater evaporate.
3. Basalt Columns: While typically hexagonal, some basalt columns can have cross-sections that appear more square-like, depending on the cooling process and the specific crystalline structure of the rock.
4. Tessellated Pavements: These are naturally formed flat rock surfaces that crack into nearly square shapes due to the contraction of the material and erosion processes. They can be seen in certain coastal regions.

Most other square shapes observed in nature are the result of human intervention or are merely approximations of squares. The preference for squares and right angles in human constructions is largely due to practical and aesthetic considerations, as these shapes are easier to work with and predict in terms of structural integrity and arrangement.