How do you extract Copper from Copper Coated Aluminum Wires?

I have some copper coated aluminum wires and I read that around 10-15% of it is copper. Although that may not sound like a lot, it may add up depending on how much one has. Anyway, perhaps there's a way to extract copper from copper coated aluminum without the use of any acids or electrolysis...

Will I be able to take my electric furnace to Al's melting point, remove any slag, pour the Al into molds... then do a second melt but this time with the slag and at copper's melting point, perhaps add some Borax and remove any Al oxide and other dross, and end up with copper in the resulting pour?

Thanks in advance!