Calcium

Calcium is the element that builds your bones and teeth. It is the most abundant metal in the human body, and without it, your skeleton would be as floppy as a jellyfish. Humphry Davy isolated calcium in 1808, though humans had been using calcium compounds like limestone and marble for thousands of years to build everything from the pyramids to the Parthenon.

Calcium is the fifth most abundant element in Earth's crust. Chalk, limestone, and marble are all forms of calcium carbonate. Calcium is added to many foods and supplements because growing kids and adults alike need it for strong bones. Calcium compounds are also used in cement, making calcium essential for the construction industry.

Calcium's symbol 'Ca' is a top-tier element for Spellement. It matches the start of words like 'cat,' 'car,' 'cake,' and 'camera,' aligning with one of the most common two-letter combinations in English. This makes it a natural favorite for element-based word spelling.