Glossary of Mining Terms SEC,Hedging Taking a buy or sell position in a futures market opposite to a position held in the cash market to minimize the risk of financial loss from an adverse price change Hematite An oxide of iron and one of that metals most common ore minerals High grade Rich ore As a verb it refers to selective mining of the best ore in a deposit...As a leading global manufacturer of crushing equipment, milling equipment,dressing equipment,drying equipment and briquette equipment etc. we offer advanced, rational solutions for any size-reduction requirements, including quarry, aggregate, grinding production and complete plant plan.