Its an issue with the Nether Ores mod itself. If you mine an ore block while its going to explode you get that broken tin. It will have the texture of whatever ore it was originally, but it will say its tin. However, it won't stack with 'real' nether tin, and it won't smelt or do anything. It is a broken ore that was set to explode, and you mined it instead. |
Like I said, its the mod itself and has nothing to do with Tekkit or the bukkit port or anything, this behavior happens in SSP as well.