Bronze is the most common metal utilized in the Desert of Demons. This was not always so. It is said that Uz of Uz, First King of Uz, had not yet lost the secrets of making steel and the other strange alloys utilized by humans in the antediluvian eons. He made metal men from strange silvery stuff and imbued them with life. Other such works of wonder can be found throughout the Desert of Demons, though whether or not they are antediluvian or products of this new world is debated heavily.
No one knows precisely how the Desert, or indeed other civilized lands, came to possess bronze. Of course there are veins of it in various mountains and other locations throughout the world, but according to scholar's reconstructions of ancient times there should be no metal left within the Earth at all. So great were the mines of the antediluvian kings, if indeed they were kings, they took all the metal that could possibly be gathered by man. Still bronze exists. Whether or not this "bronze" is the same bronze used by the peoples of our antiquity is difficult to say.
For game purposes, most melee weapons presented in the White Box also appear in Uz, but they are all made from bronze. I will possibly make an exception for Ilionians, who I imagine are more Archaic Greeks than Bronze Age ones. I admittedly use an abstract system where large weapons deal 2d6 (take the highest), medium weapons do 1d6, and small weapons do 2d6 (take the lowest). The most common weapons are spears and stabbing swords such as the xiphos, but khopeshes are still in some use, especially in Almodad. If a person wielding a bronze weapon fumbles against an opponent using an iron weapon, their weapon breaks.
There is no mail or plate armor in this setting. Instead they are replaced by bronze scales (used over leather or a linothorax) and a bronze breastplate or similar armor respectively. A warrior wearing "plate" would be wearing something like this:
the helmet is made out of boar tusks
Someone wearing scale would have something more like this:
More fantastic metals likely exist, but I'll save that for later.