The concept of gold filled jewelry is an interesting one. By definition, gold filled jewelry contains 1/20 of its respective weight in gold. It is actually a thick layering, not a plating, of actual gold over a base metal. Is is far superior to gold plated jewelry because the gold doesn't generally wear off like plated jewelry - the gold is too thick to wear through! Thus you find beautiful examples like this one where the bracelet is in amazing shape though about 100 years old. Hallmarked 1-20-10K. That means gold filled, or covered in a layer of 10 karat gold. Very beautiful and has a brand new 14K gold safety chain to boot! Circa 1900.
A Nice Antique Gold Filled Bracelet with Safety Clasp