The Diamond Desert is in fact a place with very few diamonds indeed, but every imaginable semi-precious stone that can be imagined upon it's surface. In the summer, the heat can be bad enougth to threaten life-in the winter, it is best to wear small pieces of Helspar within your clothing. There is water to be found but it is limited.The Silver River provides water, but there is the risk of being attacked by crocodiles and other dangerous river fauna whilst collecting it, or of being poisoned by parasitic worms if it is not boiled first.
The tall multi-coloured cacti that grow along the river banks, have spines that can leave septic wounds from the smallest scratch, and even if one can get the water from it, the cacti has made it poisonous, so within an hour of drinking it, it leads to sickness. There are tiny desert plants that have water within them that can be drunk without any problems, but they look just like semi-precious stones so they are very hard to find.There are a few water-holes and fertile regions but they are guarded by the Akulu, the tribal people of the region, who live here mainly because most other places have been settled by others,and distrust all desert travelers. The worst crime possible amongst the Akulu is to deliberatly poison a water-hole, and water can be spent like money, although there is little to buy with it.Along the coast there is dew at dawn which can, be those who know how to catch it, be trapped and drunk.
The myth of how it was created was that a thousand years ago the court wizard of King Amalric cast a spell to bring the diamonds of the region to the surface, but the spell went dreadfully wrong and tore up the whole area, making it unliveable in by most people, and destroying the cities and towns of the region, and that the wizard's ghost still haunts the region.
Apart from the small and scattered groups of Akulu people, only a few diamond searchers and explorers enter this place of heat and cold. Criminals are sometimes sent into it as well, with enougth water for one day.
OOC-I have a region but not the slightest idea of any story to go with such an inhospitable place.