Serching for plugin

Hi!
Im serching a plugin witch disables items form ores, for example, i need to disable diamonds falling out from diamond ores but the diamonds needs to be usable if i give them for someone... so the plugin cant block the item permanently.
well i didnt find something like this in bukkit plugin list
mby someone else can find it?
or mby you know something similar to this,,
[sorry about the rly bad english]