From Wikipedia on bones:
Bone matrix is 90 to 95% composed of elastic collagen fibers, also known as ossein,[5] and the remainder is ground substance.[6] The elasticity of collagen improves fracture resistance.[7] The matrix is hardened by the binding of inorganic mineral salt, calcium phosphate, in a chemical arrangement known as bone mineral, a form of calcium apatite.[9]
So the statement is a bit faulty, not only because of the relative low amount of calcium in our bones, but also because it appears as a mineral. We distinguish between salts and metals because of their chemical properties being quite different (solubility, reflectiveness, electrical conductivity, maleability and so on).
Edit: I do realize the point of the comment was not to be entirely factual, so if I am allowed as well I would say science is pretty metal.
There is about 8.1 billion people in the world. Assuming romantic cliches to be true and that we all have exactly one soulmate out there, we would have a very hard time sifting them out. If you were to use exactly one second at meeting a person it would take you 257 years to meet everyone alive on earth at this moment, which due to human life span being significantly shorter and the influx of new people makes the task essentially impossible without a spoonful of luck. Moral of the story: If you believe you have found your soul mate, be extra kind to them today.