Keep an object as a keepsake
Conservation protects an item from ordinary use and consumption.
Use Set keepsake on an owned individual object to conserve it. The game removes it from an equipped slot and ordinary working use while preserving its identity. Conservation does not create a second copy.
Return the object to working use before equipping it or using it as a material again. An item with sentimental importance can therefore remain in your history without silently becoming fuel or a crafting input.
A keepsake and a facility display are different forms of custody. A displayed item has been physically moved to display space; a conserved item is protected from the ordinary operations that check its keepsake status.