Beautiful rhinestone puffed heart necklace

Sparkling heart with amber rhinestones ringed with clear rhinestones. Bale and chain are marked otc 18k gep bz. Chain is also marked with a C. Chain measures approximately 18", heart is approximately 1" x 1", with an additional 3/8" from the bale. In excellent vintage condition, all stones are present, gold plating all intact. There may be minute scratches from age but I find none.