Reverse Circulation (RC) – RC drilling is the most common type of drilling undertaken and is typically used to drill to depths of approximately 400 metres. RC drilling is generally faster than diamond core drilling and generally produces better samples and better penetration than rotary air blast drilling (RAB). This method is more expensive then Air-core drilling but less expensive than Core drilling. RC drilling produces rock chips rather than core. This method collects samples from depth by pulverizing the rock which is then blown up through an inner tube and collected in a sample bag. This method is often used for reconnaissance and exploration drilling. Geodrill provides RC drilling using the latest Face Sampling hammers & equipment drilling holes with 140mm dia. to depths of between 50 – 400 meters.