14k gold pendant: worth the purchase?

[fiona00004]

I am considering purchasing this pre-loved 14k pendant. I might replace the jade with something else.

What could be causing the darkening in the gold? Is it dirty? tarnish? Old enamel? Currently priced at under $200.

Good deal? A pass?

I don't think it's actually a "Reed and Barton" product because they mostly sell silverware or electroplated jewelry...

Your PS thoughts?