Abstract: A measurement tool for use in pneumatic percussion drilling comprises a body comprising one or more measuring instruments positioned in a drill string above a pneumatically operated hammer of the drill string.

Abstract: A damper apparatus for use in pneumatic percussion drilling comprises a body having one or more damper apparatus supporting a measuring instrument. Each damper apparatus dampens shock/vibration from the pneumatic percussion drilling that is experienced by the measuring instrument.

Abstract: A drill rod for transferring torque comprises a casing for connection in a drill string. The casing is coupled to an internal body by a torque transferring mechanism at each end of the casing such that torque applied to an end of the drill rod is transferred through both of the casing and the body.

Abstract: A drill rod comprises a body comprising one or more fluid supply channels, a fluid return channel and one or more compartments.

Abstract: In one aspect, a system (5) for use in providing an approximation or estimation of a characteristic (for example, a bulk density value) of a deposit subject to a drilling operation is disclosed. In one form, the system (5) comprises a processor module (25) arranged in operable association with a network of sensors (30) operable for measuring one or more parameters relating to the operation of the drilling assembly (10). The processor module (25) is configured operable for receiving data/information derived from the network of sensors (30), and processing the data/information so as to provide a representation of the incursion (eg. depth of penetration into the relevant deposit) achieved by way of the drilling assembly (10).