Game doesnt allow to hide some treasure icons on minimap (like Tuskarr Tacklebox), but u can change their colors, by placing same icon with different color over original ones.
U can set custom color for treasure icons on minimap, like Tuskarr Tacklebox, Expedition Scout's Pack, Disturbed Dirt, Magic-Bound Chest - In Custom Options change colors and add/remove any other minimap icon (by its name)
Requires 'HereBeDragons' library to work - it commes with addons like HandyNotes, TomTom, SilverDragon, but if u dont have any of those addons, just install 'HereBeDragons' from Curse.
May not work with ElvUI.