How to delete Items from inventories and boxes?

I ran into a problem due to the fact that metal - refined will be used with todays update. I use it as currency on my server and want to exchange it with another item plus delete the remaining metal - refined on the server without been forced to wipe the whole thing. Is there any plugin that can help me to deal with that situation ?

 

I've looked on all the plugins and from memory there isn't anything that removes items like refined metal. I know you can remove things you place but what you have Im pretty sure there is nothing out there.

 

does anyone know the item name for high quality metal ?

 

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