All that Glitters (2003)

From "Adventure Summary and Background:"

A hundred and fifty years ago, the pirate known as Captain Khardin plundered his last ships - a trading convoy carrying goods from Khitan. The convoy also carried the august personage of Garniss the Sage, a noted diviner and researcher of many new and unique spells.

After looting the ships, Khardin hid the treasure and left a stone carving in the care of his mistress detailing where it could be found. Then he sailed off for one last raid before the rainy season began - and never returned.

His mistress was killed by a rival pirate seeking Khardin’s plunder, and he was unable to decipher the stone. So it passed from hand to hand until it finally came to the Temple of Althares some thirty years later, where it was duly cataloged and its legend noted, and that was the end of it - except for the occasional band of adventurers to come along and try their hand at the puzzle.

About twenty years ago, one such band came and made a rubbing of the stone, intending to take it to a noted Loremaster in Althares itself. They succeeded, and received a cryptic verse from the Loremaster’s legend lore, but before they could return to seek the treasure, half the party was wiped out saving a small village from a Ss’ressen incursion.

The fragments of their notes, however, survived until the present day, where they are found by the PCs.