Mining in Manitoba




Mining Systems



Blasting theory

Drill Patterns

Blasting Cycle


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Explosives may be either high or low depending on the manner in which the explosion takes place. Both detonations and deflagrations are explosions of a chemical nature and the over-all reaction is exothermic.

High explosive - detonates when it is properly primed and an explosion is initiated in it.

Low explosive - does not exhibit a shockwave in the explosive but burn at a high rate.

Detonation - the process of propagation of a shockwave through an explosive.

Some of the properties of high explosives that are important in blasting are density, velocity of detonation, temperature and pressure of the "detonation state", heat of the explosion, and available energy. The density is determined largely by composition and manner of packaging. The velocity of detonation is the only property which can be readily measured.

Detonating explosives are usually subdivided into two categories, primary and secondary. Primary explosives detonate by ignition from some source such as flame, spark, impact, or other means that will produce heat of sufficient magnitude. Secondary explosives require a detonator and, in some cases, a supplementary booster. A few explosives can be both primary and secondary depending on the conditions of use.

  Black Powder

Liquid Oxygen
Nitro Starch
Water Gels