The Necropolis
A tomb east of Klysma Quarry. You'll go through here during the 'Howls of the Dead' Side Quest.
There are two treasures to loot. One you'll find during the side quest, through a low tunnel beneath a flapping red cloth.
You'll pass through a chamber strewn with rent limbs, but also one of the location treasures. So, sun and rain.
The other treasure is also off the main chamber, hidden behind some flapping red cloth. This time it's a larger, slightly less flappy weaving, hanging between two sarcophagi.
Break through the panel behind the cloth to reveal a small subchamber, with a small box of carbon crystals.
Loot the box to complete the location.