This is a very large authentic antique maritime deck prism circa 1800's . It was made to capture and spread light in through the cabins below decks. Without light shining through it has a purple tinge formed by the lead content which makes it very strong. As light pours through it radiates green and blue translucent shimmers, very beautiful and strange. This is a real authentic antique deck prism not like the flood of cheap replicas on sale all over the internet. This is a very rare glass objet d'art. its 15 cm in circumference and 14 cm deep. Its big.
