Zinc

In nature, zinc is found in the Earth's crust, 200 ppm, in minerals such as smithsonite/zinc spar, sphalerite/zinc blende, zincite, willemite, franklinite and gahnite [7]. The isotopes found in nature are ⁶⁴Zn (48.89 %, stable), ⁶⁶Zn (27.81 %, stable), ⁶⁷Zn (4.11%, stable), ⁶⁸Zn (18.57 %, stable) and ⁷⁰Zn (0.62 %, stable) [7].

In pure solid form, zinc exist in a hexagonal close-packed crystal structure [2].