which weapons can be upgraded?

Hi. got a newb question here. what kind of weapons can be upgraded with components like hilt and pommel?

like a sword, can i use pommels and hilts on a purple or gold or green sword?

if i used a pommel on a sword, can i put another pommel to replace the old mod?
thanks.

Guildwiki has this information in detail. In brief, Swords, Axes, Hammers and Staves can be modified with upgrades. Greens are an exception as they cannot be modded or salvaged. Applying a new mod will replace the existing one.

Anything except Greens, Focuses, Shields and Wands/Rods.

k thanks for the info!