The Civil Guard raided the man's home in August, finding maps of archaeological sites and a helmet "very similar to some Celtiberian pieces auctioned in Munich" that were thought to have been smuggled out of Spain at one point, TheLocal.es reported Tuesday.
Experts were analyzing the pieces -- some of which were in poor condition -- to determine their exact origin, El Pais reported.
The man, whose name wasn't reported, was charged Aug. 4 with crimes against Spanish heritage, TheLocal.es said.
Police said the man was an accomplice of Ricardo Granada, who allegedly smuggled the helmet out of Spain to Germany for auction.
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