Name/Title
Clam (fossil)Entry/Object ID
78.57.138Description
Crystal System: Hexagonal System
Description: Phylum: Mollusca
Class: Pelecypoda
Subclass:Brachiopoda
Common Name: Fossil Shells
Age: Un-determined
Location:Yellow River, Montana
Description:One group of bi-valved shells in concretion. Coated with mother of pearl showing concentric ridges.
Physical Characteristics:
A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk. In life, the shell of this class of mollusks is composed of two parts, two valves which are hinged together. Bivalves are very common in many kinds of saltwater habitats, but they are also found in brackish water and in freshwater.
Bivalves are a common part of the marine fauna worldwide (scallops, clams, oysters, mussels, etc). The shells of marine bivalves commonly wash up on beaches (often as separate valves) and the shells of freshwater species can sometimes be found along the flood plains of rivers, and other freshwater habitats.
Bivalves typically have two-part shells, two valves, that are joined by a ligament. The two valves usually articulate with one another using structures known as "teeth" which are situated along the hinge line. In many (but by no means all) bivalve shells, the two valves are symmetrical along the hinge line.
This exoskeleton serves not only for muscle attachment, but also for protection from predators and from mechanical damage. The shell has several layers, and is typically made of calcium carbonate precipitated out into an organic matrix. It is secreted by a part of the molluscan body known as the mantle.
Fracture: Conchoidal
Genus: Pelecypoda
Grain Size: Fine
Hardness: 3 Calcite
Kingdom: Animalia (Animals)
Luster: Vitreous
Class: Cephalopopda
Phylum: Mollusca
Rock Origin: Terrestrial
Rock Type: Sedimentary
Streak: whiteCollection
Fossil CollectionAcquisition
Accession
78.57Source or Donor
Delmar Smith Fossil CollectionAcquisition Method
DonationDimensions
Width
5-3/4 inLength
4-1/2 inLocation
Location
Container
RightDrawer
Bottom ShelfShelf
Left, LeftWall
WestRoom
Fossil RoomBuilding
Crater Rock MuseumCategory
PermanentMoved By
Steve MillerDate
May 29, 2012Location
Container
LeftDrawer
2nd ShelfShelf
RightCabinet
Case # 2Wall
WestRoom
Fossil RoomBuilding
Crater Rock MuseumCategory
Permanent
