The Ore Sniffer is a block that scans the area around it and marks the ore and minerals for you. When you place it down, it scans a 13x13x13 area around it. You can also configure what to display when you right click on the Ore Sniffer. (Toggle the ores/materials on and off, as well as distance). Everything should work fine on SMP.
How to install:
- Download and install Minecraft Forge.
- Download the Ore Sniffer Mod from link below.
- Go to .minecraft/mods folder. If the "mods" folder does not exist you can create one.
- Windows – Open the Start menu and select Run, or press the Windows key + R. Type (without quotes) "%appdata%\.minecraft\mods" and press Enter.
- OS X – Open the Go menu in Finder and select “Go to Folder”. Type (without quotes) "~/Library/Application Support/minecraft/mods" and press Return.
- Copy the downloaded jar (zip) file into the "mods" folder that opens.
- Enjoy the mod.