This $20 Liberty Gold piece was double struck in the collar, rotating a few degrees counterclockwise between the strikes. LIBERTY, the date, the obverse stars and the portrait exhibit a wide spread between the strikes. The second strike on the reverse is less obvious but visible upon closer inspection.

I recently sold the other known double struck (actually triple struck) $20 Liberty Gold piece that was certified MS 63 by PCGS for $102,500.