Large treasure appears in one place on the quest. Each run has ten pieces which, from what I've seen, is grouped in sets of ten; the sets appear to rotate. Some items are grabbags - container with contents.
Set 1
a polished animite ring set with a miniature crossbow
a pale avaes lens
an olive leather backpack embroidered with a golden wolverine
a supple firesilk thigh pouch with flames lightly embroidered along the straps
a black silk carryall clasped by a dainty ruby flamerose
a dark crystal circlet embedded with many faceted blood-red rubies
a hollow crystal armband filled with glittering gemstones
an inconspicuous embossed leather wrist sheath
a lanahh pahapo
a deep black onyx coffin set with delicate pink erythrite roses
Set 2
Note: To my knowledge, this set only appeared on run 2.
a purple jade jewelry box etched with fine silver veins
a heavy animite ring set with an uncut blood-red ruby
a dark steel boko crafted to resemble a skull
a hand-tooled leather harness
an aged bronze helm covered in sickly green patina
a braided leather greatsword sheath
a platinum-hilted bastard sword engraved with the image of a flaming comet
a pearl and gold net girdle
a pearl-inlaid platinum flute
a polished steel shotel with a black pearl pommel
Set 3
a blackened nimsha etched with a silver labyrinthine pattern
a double tiered tiara of highly polished platinum centered with a large nightfire opal
a voluminous sea green watersilk cloak edged with tiny white seed pearls
a polished platinum jewelry box carved with curling vines of Elven ivy
a split-blade dagger
a brushed animite band set with a perfect serpent's heart ruby
a slender golden circlet from which dangle hundreds of multihued sapphires
a stuffed colorful parrot
a simple dragon's scale sapphire pendant
a darkened composite bow etched with slender panthers