Marco Polo's Voyage to Indian Seas: 17: Island of Seilan [1]

When you depart Angaman, and sail about a thousand miles westward a little to the south you reach the island of Seilan, the very best of its size in the world.  The island is 2400 miles in circuit; yet I must tell you that anciently it was larger, being 3600 as appeared by the old maps of  mariners on that sea, but the north wind blows with such violence, that a great part has been carried away by the water. The people have a king called sendemain, and is tributary to none.  The people are idolaters and go quite naked, except a small covering round the middle. They have no grain except rice, and they live on rice and flesh.  I will now describe the most precious thing in the world: here are noble and beautiful rubies, which can be procured nowhere else.  Also the sapphire, the topaz, the amethyst and various other precious stones.  The king has the most beautiful Ruby that ever was or can be in the whole world.  It is the most splendid object on earth, and seems to glow like fire. It is of such value as money could scarcely purchase.  The great Khan sent his messengers to him, wishing to buy it and offering the value of a city.  The king replied that he had received it from his ancestors, and would not part with it for any earthly consideration.  The people are not men at war, but unwarlike and cowardly; when the king need soldiers they got it from other countries, commonly Saracens.

Note:-

1. Seilan: Ceylon of the recent past or the Modern day Srilanka.