Invalid registration attempt

[19:37:16] [Client thread/WARN] [FML]: ****************************************
[19:37:16] [Client thread/WARN] [FML]: * Invalid registration attempt for an Ore Dictionary item with name stone has occurred. The registration has been denied to prevent crashes. The mod responsible for the registration needs to correct this.
[19:37:16] [Client thread/WARN] [FML]: *  at net.minecraftforge.oredict.OreDictionary.registerOreImpl(OreDictionary.java:483)
[19:37:16] [Client thread/WARN] [FML]: *  at net.minecraftforge.oredict.OreDictionary.registerOre(OreDictionary.java:469)
[19:37:16] [Client thread/WARN] [FML]: *  at com.gamebuster19901.Main.init(Main.java:37)
[19:37:16] [Client thread/WARN] [FML]: *  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[19:37:16] [Client thread/WARN] [FML]: *  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
[19:37:16] [Client thread/WARN] [FML]: *  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)...
[19:37:16] [Client thread/WARN] [FML]: ****************************************