Madrepore

The beauty of the madrepores and corallines, of which the finest specimens are found in the recesses of the Bay of Tappanuli, is not to be surpassed in any country.

The rocks of Gonye are reddish gray sandstone, nearly horizontal, and perforated by madrepores, the holes showing the course of the insect in different directions.

This bay is approached from the choir by the first marble step which is in Frosterley, a marble with beautiful madrepores of light colour on a dark ground.