How much gold can I receive for each chest/skull/commodity?

This is what I've seen either in-game or by reading about the game on The Internet. Some data is missing; I'll edit this answer as I learn more.

Chests

Name                             Sale Price 
-------------------------   ---------------
Captain's Chest              ~600-1020 gold
Castaway's Chest               ~70-130 gold
Chest of a Thousand Grogs*   ~840-1470 gold   
Chest of Sorrow**            ~800-1540 gold
Marauder's Chest              ~300-520 gold
Seafarer's Chest              ~140-260 gold
Stronghold Chest            ~1420-3340 gold

* causes carrier to be drunk
** cries occasionally and fills ships with water

Commodities

Name                    Sale Price   Sale Price (quest)
----------------   ---------------   ------------------
Chicken                                       
    Black
    Gold            
    Red
    White           
Exotic Silks         ~570-920 gold
Exquisite Spices   ~1240-1860 gold
Fine Sugar           ~140-230 gold
Gunpowder Barrel      ~80-180 gold
Pig     
    Black
    Gold
    Pink
    Pink & Black                  
Rare Tea             ~260-560 gold
Snake                                         
    Black
    Blue
    Red
    Yellow         

Skulls

Name                    Sale Price
----------------   ---------------
Disgraced Skull      ~190-350 gold
Foul Skull           ~100-170 gold
Hateful Skull        ~401-690 gold
Villainous Skull    ~910-1350 gold
Stronghold Skull   ~2310-3950 gold

Miscellaneous

Name                Sale Price       Faction
----------------   ---------------   ---------------
Silver Chalice     ~250 gold         Gold Hoarders

Reference

• Treasure Chest
• Rare Tea Crate
• Bounty Skulls
• Quick Guide to Merchant Quests
• Sea of Thieves Loot Values (spreadsheet)