A geologist's hammer, also known as rock hammer, rock pick, geological pick, or geo pick, is a specialized hammer used for splitting and breaking rocks. In field geology, it is employed to expose fresh rock surfaces, as weathered surfaces may obscure accurate analysis of a rock's composition, bedding orientation, mineralogy, history, and strength.[1][2] In fossil and mineral collecting, geologist's hammers are used to break rocks in order to reveal specimens contained within.
![]() A typical geologist's hammer | |
Classification | Hand tool |
---|---|
Uses | Sample collection |
Types | Chisel head Pick head |
Used with | Drilling hammer Cold chisel |
Related | Hammer |
Geologist's hammers, as with most hammers, have two heads, one on either side. Most commonly, the tool consists of a flat square head on one end, with either a chisel or a pick head at the other end.[3]
The effective power of a geologist's hammer is mainly considered to be a reflection of its head weight and handle length. Head weight may range from 8 oz (230 g) or less on a small hammer—such as would generally be used for casual use or by children—to 4 lb (1.8 kg) and greater. A hammer of 2–2.5 lb (0.91–1.13 kg) has been described as most useful,[3] although metamorphic or igneous rocks often require heavier hammers for a more powerful blow. In such cases geologists may prefer a sledge or bricklayer's "club" hammer.[3]
The best geologist's hammers are forged from one piece of hardened steel, which renders them sturdy and long-lasting. Alternatives such as tubular- and wooden-shafted hammers are more commonly used,[3] in part due to their lower cost. Such alternative handles sacrifice strength and make the hammer unsuitable for high-strain activities such as prying.[citation needed]
The form and weighting of the shaft defines the balance, which itself defines the ease, efficiency, and comfort of use of the geologist's hammer.[citation needed]