This Tumidocarcinus giganteus crab is unprepped and as I found it, still mostly in the concretion, with a part of the carapace and one claw showing.
You can see the leg rings on either side which is usually how I can tell there is a fossil crab inside. There are a few barnacles growing on it showing that is must have spent a fair bit of time in the water before I found it.
Photogrammetry was used to create the 3D model.
Age: ~12 million years old (Miocene)
Location: South Island, New Zealand
Size: 16cm long, 13cm wide, 8cm high (6.2" x 5.1" x 3.1")
Weight: 2.08kg (4.6lbs)