Although it’s one of Starsky’s most iconic accessories, the simple necklace made of black double string (possibly leather cord) and replicas of ancient Chinese bronze coins only appears in the latter half the show, in 03-01 “Starsky and Hutch on Playboy Island”. Then it is seen in almost every S3 and S4 episode. It’s there on Starsky’s neck even when he’s in the ICU in “Sweet Revenge”! I currently think that the only episode where Starsky doesn’t wear it is 03-05 “Murder Ward” – not even in the tag, when Starsky is no longer undercover in the mental hospital, just visiting.
But are there two or three coins on the necklace? I can’t decide. Most of the time it looks like two, but sometimes like three (even within the same scene, so it’s unlikely there were different versions, and anyway it looks like Paul Michael Glaser rarely took the necklace off once he made it in 1977). Maybe the third coin in the middle is smaller, which might explain why it’s rarely seen? I’ll have to keep my eyes open for better photos.
It’s also impossible to tell what exact symbols the coins have, but the coins look roughly like this, with symbols on all four sides of the square hole (at least on the sides that are visible; the other side could be different). Similar coins are easily available – look for Feng Shui coins, I Ching coins, or just Chinese lucky coins.