In particular, I thought this community would find this article interesting: a cultural guide to having chai [tea] in Afghanistan.
It includes information on the tea itself:
Sugar is nearly always available, and its absence will bring a strong apology. When Afghans put sugar in their chai, they put sugar in their chai. There will be a layer at least a quarter of an inch deep left in the bottom of the cup after the chai is poured.
Chai is always served absolutely scalding hot. The chai itself is usually green, but sometimes will be black. It is made by putting the tea leaves in the pot and boiling the water, often on a burner sitting directly atop a propane cylinder. If they are making shiir chai (milk tea) the leaves are put into the milk directly and the milk is not quite boiled.
And etiquette tips:
Weapons should be lain at your side with the muzzles pointed away from the center; a gesture of good will. Pistols should remain holstered. It is not appropriate to handle your weapons while drinking chai unless it is to make room for someone else.
I found this fascinating. Hope you like it!