Heist loot symbols?

Is there a guide somewhere that explains the little symbols that show up on chests, on the heist maps? I assume they have something to do with type of loot the chest is likely to drop?

They are the same symbols that are used in Metamorphs, Blight, Legion and Delirium encounters, plus a new symbol, the Delirium Reward, which is the same icon used for the Delirium Mirror on minimap: The horns of Tangm- erm, Strange Voice (Or 12Challenge Reward from Delirium League, if you like it better).

I've also just noticed they are also the same symbols used in DeliOrbs and Incubators to associate them with a specific reward.

The reward is chosen at random in a poll of possible rewards, and you cannot foresee this reward. The only exception is in Metamorph encounters, where you can see exactly what organ will give you what kind of reward

If you still need a graphic, here is what I've polled by searching the wikia and making a very ugly patchwork because apparently I cannot download Icon symbols from there



1 - Abyss (Abyss Jewels, Stygian vise)
2 - Armour (Generic armour/Shield, Armour/Shield with Incursion modifier, Shaper/Elder Armour/Shield, Veiled Armour/Shield)
3 - Bestiary (Bestiary Scarab, Item with random Aspect)
4 - Breach (Breach splinter, Breach Ring, Breach Scarab)
5 - Currency (generic currency, valuable currency*, Currency fragments)
6 - Divination (Stacked Deck, Divination Card, Divination scarab)
7 - Essence (Essence, Remnant of Corruption)
8 - Fossil (Fossil, Resonator, Sulphite Scarab)
9 - Map Fragment (Sacrifice Fragment, Mortal fragment)
10 - Gems (Skill and Support gems, 20% Quality Gem, lv20 Gem, Valuable gem**)
11 - Generic (Any from Armour, Currency, Jewellery and Weapon rewards)
12 - Harbinger (Beachhead, Currency Fragments, Valuable Currency Fragments***, Harbinger scarab)
13 - Labyrinth (Offering to the Goddess, Item with Merciless/Eternal Labyrinth Enchantment)
14 - Map (Sextants, Cartographer's Chisel, Maps, 8-Mod Corrupted Map, Cartographer Scarab)
15 - Perandus (Perandus coins, Perandus coins + Cadiro spawn, Perandus Scarab)
16 - Prophecy (Itemized prophecy, Pale Court key, Silver ring)
17 - Scarab (any scarab)
18 - Talisman (Tier 1,2 or 3 Talisman, Unique non-Tier4 Talisman)
19 - Jewellery (generic Jewellery, Jewellery with Incursion modifier, Shaper/Elder Jewellery, Veiled Jewellery)
20 - Unique (Unique item, Unique items, 6-Linked Unique item, Reliquiary Scarab)
21 - Weapon (Generic weapon, Weapon with Incursion modifier, Shaper/Elder Weapon, Veiled Weapon)
22 - Blight (Oils, Blighted map)
23 - Delirium (Delirum splinters, Cluster Jewel)
24 - Metamorph (Catalysts)

* Valuable currency are: Exalted Orb, Mirror of Kalandra,
** Valuable gems are: Enlighten, Enhance, Empower
*** Valuable currency fragments are: Exalted shard, Mirror shard, Harbinger shard, Ancient shard

(Reward pool updated since Delirium. Heist reward may have further rewards)

Awesome - thanks, man, that was exactly what I was looking for!

Still pretty new at this - only started playing a couple days before Heist League started, and only in the beginning of Act 2 so far. I have yet to experience any of those things you mentioned (Blight, Legion, etc), so the only place I've seen these symbols is in Heists. :)