Bivalve Fossils
Bivalves appear in the fossil record first in the early Cambrian more than 500 million years ago. Bivalves as a group have no head and they lack some usual molluscan organs. The shell of a bivalve is composed of calcium carbonate, and consists of two, usually similar, parts called valves. These are joined together along one edge (the hinge line) by a flexible ligament that, usually in conjunction with interlocking "teeth" on each of the valves, forms the hinge. This arrangement allows the shell to be opened and closed without the two halves detaching.
Rastellum "Alien" carinatum bivalves
Rastellum carinatum is a Cockscomb Bivalve from Northern Madagascar and is Cretaceous in age. Has a typical bivalve zig-zag appearance of where the two valves shut. Found in Marovoay, Mahajanga district. Many people call these "Aliens". Size is typically 70-90mm on average, see the photo for scale
Shell Jasper from Madagascar
Shell Jasper, cut and polished rock slices. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Polished Shell Jasper Slice 1
£11.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 13.0cm long.
Size: 13.0cm long.
Polished Shell Jasper Slice 2
£10.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 9.0cm long.
Size: 9.0cm long.
Polished Shell Jasper Slice 3
£11.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 10.5cm long.
Size: 10.5cm long.
Polished Shell Jasper Slice 4
£9.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 10.5cm long.
Size: 10.5cm long.
Polished Shell Jasper Slice 5
£6.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 9.5cm long.
Size: 9.5cm long.
Polished Shell Jasper Slice 6
£11.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 12.0cm long.
Size: 12.0cm long.
Polished Shell Jasper Slice 7
£11.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 11.0cm long.
Size: 11.0cm long.
Polished Shell Jasper Slice 8
£11.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 11.5cm long.
Size: 11.5cm long.
Polished Shell Jasper Slice 10
£11.99
A lovely piece of Shell Jasper, cut and polished rock slice. This is full of sea shells, the fossilized remains of bivalves and gastropods. It has really great contrast. Found in Madagascar. Makes a great display.
Size: 13.5cm long.
Size: 13.5cm long.
