Golden Caveling Mask金色のケイヴリングマスク

An intricate mask with a stern expression, it was probably used in a ritual or by someone of high ranks.
In-game description

What is Golden Caveling Mask? Features and uses

Golden Caveling Mask is a poor item in Core Keeper (Valuables). It can be obtained from Archeologist Wall Loot.

Golden Caveling Mask key points (from the game data)

Best source: Archeologist Wall Loot — 5.3% chance per roll.
Sells to merchants for 89 Ancient Coins.

Calculated and summarized by this site from the game data (1.3.0.6).

How to get Golden Caveling Mask (Mining walls)

Mining walls (1)

There are also sources whose in-game name has not been confirmed yet (Mining walls: 1).

"Chance" is the chance to get at least one of this item per try (opening one chest, defeating one enemy, one catch). A "guaranteed group" is the group of a chest or boss from which exactly one item always drops; it does not mean this item always drops (the chance of it being picked from that group is shown in small text). Only items that always drop are marked "Guaranteed". Fishing means catches with a fishing rod, separate from enemy and boss drops. Calculated from the game's drop tables (Conf/Loot, 1.3.0.6) the same way the game rolls them.

Other ways to get Golden Caveling Mask

Placed in or on the Boss Chest found inside a scene (building, ruin, camp and so on) (guaranteed)Where: City Hall [Sunken City]
Placed in or on the Boss Chest found inside a scene (building, ruin, camp and so on) (guaranteed)Where: Glyph Parchment Treasury [The Sunken Sea]

Scene containers, dungeon placements, guaranteed drops and natural spawns are based on the Obtaining data of the Core Keeper Wiki (Fandom) (CC BY-SA 3.0), because these are not in the game files this site reads. Scene names are the wiki's English names.