Here is a lovely antique 14k solid gold flat curblink chain. This chain feels fabulous on with a significant heft to it. The was most likely a fob chain that had 1.5" extension added at a later date but is a perfect match to the original links.

The actual chain measures 13" with a 7.7 mm jump ring attaching the additional 1.5" chain to it giving it a finishing length of 16" but can be worn as a choker.

Dimensions: 4.8 mm wide x 2.5 mm thick
Length: 16" with spring ring clasp and dog clip swivel
Markings: 14 on dogclip
Metal: 14k yellow gold
Weight: 29 grams
Condition: 8 (spring ring shows some wear)