Items and Gold Disappear after time when left on the ground
Don't leave items or gold lying on the ground any longer than necessary, especially when transferring in town ("muling") as they disappear after a certain amount of time:
10 minutes: Key, Potion, Scroll, Tome, and Ammo (Arrows, Bolts).
10 minutes: Any Armor and Weapon of quality < magic, regardless if flagged as ''Ethereal'', ''Socketed'' or not, and Rune Words.
10 minutes: Pandemonium artifacts (Key of Terror/Hate/Destruction, Mephisto's Brain, Diablo's Horn, Baal's Eye).
10 minutes: Essence (4 flavours) and Token of Absolution (these are new items from Patch 1.13x).
20 minutes: Magic Items, Gems and Runes.
30 minutes: Rare, Set, Unique and Crafted Items.
Picking an item onto your cursor and dropping it again resets the timer.