Ellen Hall, aged 11, of Albany, N, Y,, for her question:

How did marble get its colors?

We have all admired statues and pillars of glossy white marble. liaybe we have also seen tiles and table tops make from various colored marbles. There is a green marble that looks like frozen foliage. There is a violet marble that looks like pansies pressed under glass. There is a rose colored marble that looks like icy sherbet. There are marbles of blue, brown, gray and gold.

Colored marbles almost always come in several shades. Violets are flecked with greens. Greens are often dappled with greys. Rose is often veined with brown. Some of the most beautiful marbles are simple white, strea?ced, veined and feathered with shades of grey. These blends and mixtures of tones make marble forever interesting  interesting to trace the patterns, interesting to wonder how it got that way.

All marble was made under the sea. It is formed from the shell like remains of little sea creatures that lived millions of years ago. Layers and piles of these tiny remains collected through the ages on the ocean floor. In time some of these shell coated sea beds became dry land. The new ground was covered with chalky, limy deposits,

Some of these layers dried out to form beds of soft chalk. Same hardened into limestone. Some became tough dolomite   the rocky layers that form the shelf and bed of tumbling Niagara.. All these rocks are masses of grayish white limy substance.

Some of this limestone went on to further adventures. It became pressed under heavier layers from above, It felt the heat from volcanoes, mineral springs and the heaving earth, 114uch of it was crushed and pummelled to fragments. All this torture simply made the limestone tougher. Its particles blended to form a rock whose surface could be polished to a glossy glow. It became marble.

Through the years, ground water flowed in to fill the cracks in the broken marble. And the ground water carried along various dissolved minerals. These minerals blended with the marble, changing its natural white color, host of tine color crept into the cracks, giving the marble its veins and beautiful freckles.

Oxide of iron formed marble colors of yellow and brown. Many of the red and pink tones were made by the mineral with ramite. The mineral serpentine helped form many of the lush green tones of marble. All these beautiful colors were formed by impurities mixed with the original stone. The purest marble is the whitest marble.