Calcium is odorless. It can have a solid, gray-white complexion or a softer, silver-white color.
Calcium has a hard, brittle surface that can be grounded into a fine powder. There are many other forms of calcium, including calcium-based molecules, which also have no smell. One example is calcium alginate, a natural carbohydrate extract from kelp, which has its own set of unique chemical properties that distinguish it from the basic element of calcium. Calcium alginate has a different color than calcium, appearing as a creamy, yellowish powder. In addition to being odorless, calcium alginate is also tasteless and it does not dissolve in water.