Ammonite Crabs can be found on the most coastal areas and the most northern beaches of Fossil Island. They cannot be attacked by dwarf multicannons.
Drops
Weapons
Item Quantity Rarity GE market price 
Bronze pickaxe 1 Common 67
Iron pickaxe 1 Common 24
Fossils
Item Quantity Rarity GE market price
Numulite 2–28 Common (27/175; 15%) 40–560
Unidentified small fossil 1 Rare (3/350=0.86%) Not sold
Unidentified medium fossil 1 Rare (3/700=0.43%) Not sold
Unidentified large fossil 1 Rare (3/875=0.34%) Not sold
Unidentified rare fossil 1 Very rare (3/3500=0.086%) Not sold
Others
Item Quantity Rarity GE market price
Oyster 1–2 Common 86–172
Seaweed 1–5 Common 45–225
Oyster pearl 1 Common 108
Empty oyster 1 Common Not sold
Spinach roll 1 Uncommon Not sold
Knife 1 Uncommon 98
Opal bolt tips 5 Uncommon 40
Iron ore 1 Uncommon 173
Coal 2 Uncommon 324
Copper ore 3 Uncommon 285
Tin ore 3 Uncommon 285
Fishing bait 1–10 Uncommon 4–40
Calcite 1 Rare 20
Pyrophosphite 1 Rare 71
Seaweed spore 1 Rare 964
Volcanic ash 1 Rare 68
Casket 1 Rare 731
Clue scroll (easy) 1 Rare Not sold
Gem drop table
In addition to the drops above, this monster has access to the gem drop table.
Show/hide gem drop table Item Quantity Rarity GE market price
Uncut sapphire 1 Rare 455
Uncut emerald 1 Rare 679
Uncut ruby 1 Rare 1,249
Unknown talisman
(please specify)1 Very rare Error
Uncut diamond 1 Very rare 2,627
Rune javelin 5 Very rare 875
Loop half of key 1 Very rare 10,307
Tooth half of key 1 Very rare 10,840
Rune spear 1 Very rare 11,933
Shield left half 1 Very rare 65,697
Dragon spear 1 Very rare 37,226
Trivia
- The examine is a reference to Twitch Plays Pokémon.