Miriam Morsel age 10, of Richmond, Va., for her question:

What is alabaster?

Alabaster is a beautiful translucent stone. It is not transparent but it lets through some of the light. Most of it is milky white but it may be pearly grey, tinted with pastel tones or streaked with darker grey. Alabaster is so soft that you can scratch it with a fingernail. The stony minerals are rated on a scale of hardness. There are ten classes in the scale. Number 10, the hardest, is occupied by the diamond. Number one, the softest stone is occupied by the talcs. Alabaster rates as number two on the scale of hardness.

This makes alabaster easy to carve. It is used to make statuettes and art objects. Chemically it is a farm of the mineral gypsum, one of the most plentiful of rocky substances. It is a water made substance formed from ancient seas and lagoons. As the old sea‑water dried, the dissolved chemicals within it were left behind. Some of these chemicals formed solid gypsum. The chief ingredient of gypsum is calcium sulphate. Traces of other ingredients give it delicate pastel tones.

Much of the worlds gypsum is in the form of sand. The dazzling desert of White Sands, New Mexico is made of pure gypsum. Alabaster is a solid, stony or massive form of gypsum.