question about crystalline sword drops

"Crystalline Swords are extremely rare; many players may never see one of these weapons. They occasionally drop from quest reward chests in the Underworld , Sorrow's Furnace , the Fissure of Woe , and in the Hall of Heroes."

I see this on guildwiki and it still leaves me with one small question for anyone who might know, the quest reward chest part makes me wonder if that means only quest rewards chests can drop a crystalline sword, or if any chests in these areas has a small chance to.

For example if I were to go into Sorrow's Furnace and find a random chest, would it be possible for it to drop a crystalline sword at all?

Any chest that doesn't need a key (i.e. the couple during Kilroy stoneskin) have a chance of dropping a crystalline. I actually got a cyrstalline doing killroy on my necro. HoH is the only place you can get gold/rare ones.

I'm thinking we should create a sticky thread concerning this, seeing as this question seems to pop up quite often.

As Knightsaber said, they only drop from keyless chests and HoH.