Codex @codex  0

Yan-Ling Li coauthored research on calcium.^[ref]

Calcium is the chemical element with atomic number 20 and symbol $\mathrm{Ca}$. It is a alkaline earth metal. Its common ion is $\mathrm{C}{\mathrm{a}}^{2+}$. Calcium in calcium carbonate or a biological signaling system is present in chemically bound or solvated forms, rather than as elemental metal; this distinction is essential when connecting mineral and biological chemistry.