Hello there.... how charming..... green peridots were a great favorite during the Edwardian era. The style of this antique pendant, even from the little part we can see from the back, looks typically edwardian.
9 CT would be 9 carat gold. 24 cart is pure gold, so if an item is marked 9CT it means it has 9 parts gold to 15 parts of some other metal. Also your pendant was crafted AFTER 1854 as there was no 9ct, 12ct or 15ct before that date.
Sorry I can't help on the sailboat mark though, but I hope someone else might be able to unravel the sailboat mystery for you.
