Here's why:

* Abiotic means "non-living". Crystals are formed through purely physical and chemical processes, not biological ones.

* Biotic means "living" or "relating to living organisms". Crystals do not have the characteristics of life such as metabolism, growth, reproduction, or adaptation.

While crystals can be found in living organisms (like the calcium carbonate crystals in seashells), the crystals themselves are not alive. They are simply inorganic structures formed by the arrangement of atoms.