Kim Kardashian's robbers did NOT make a clean getaway -- they dropped one item, and we've learned the blinged-out piece came straight from famed jeweler, Jacob and Co.
The recovered jewelry is a platinum mounted diamond cross ... according to our sources. Amazingly, a passerby found it on a sidewalk outside the apartment complex the day after the robbery. We're told it's worth $33,180.
Police are checking the pendant for any traces of DNA that could potentially help crack the case.
As we first told you, the robbers made off with a total of 13 items, worth $5.6 million ... and that includes the massive $4 million diamond ring.
Hard to tell if it has enough diamonds to be the actual pendant, but Kim was sporting this cross in Paris just 2 days before the robbery went down.