Fluid preservation refers to specimens and objects that are preserved in fluids, most commonly alcohol and formaldehyde, but also glycerin, mineral oil, acids, glycols, and a host of other chemicals that protect the specimen from deterioration. Some of the oldest natural history specimens in the world are preserved in fluid.
Fluid Preserved Specimens
History:
Beginning in the 17th century, researchers and museums have been able to preserve whole specimens by submersing and storing them in fluid chemicals. There are three components to a fluid-preserved specimen:
The fixed specimen: The specimen is prepared by “fixing” it, achieved by injecting it with chemicals that stop the deterioration and decay process (known as “autolysis”). The most common fixative is formaldehyde, or a formaldehyde and water solution known as formalin. Some specimens may not be fixed before being submersed in the fluid preserve.
The fluid preserve: The preserve is commonly alcohol, either ethanol or isopropyl alcohol.
The container: Containers are typically glass jars or bottles sealed with a closure. Types of closures may vary within a collection and often include lids with gaskets. Large specimens may require the use of open glass tanks.
