What are Carbonate Replacement Deposits or CRDs?
Carbonate replacement deposits (CRDs) are high-temperature carbonate-hosted Zinc, Lead and Silver deposits. These deposits require over 250 degrees Celsius of temperature to form. A CRD is an orebody of metallic minerals formed by the replacement of sedimentary, usually carbonate rock, by metal-bearing solutions in the vicinity of igneous intrusions. When the ore forms a blanket-like structure around the bedding plane of rock, it is commonly referred to as a manto (Spanish for mantle) ore deposit.
Properties of CRDs
Carbonate replacement deposits are polymetallic which simply implies that they have various metals in them such as copper, gold, silver, lead, manganese and zinc. The mineralogy changes depend on the distance from the intrusive rock. The mineralization of these deposits usually develops over as many as 7-8 kilometers from the intrusion. Closest to the intrusion is the copper-gold zone, next is the lead-silver zone, then comes the zinc-manganese zone.
CRDs deposits are epigenetic deposits, which means that they are produced on or near the Earth’s surface and not in volcanos. Many different deposits form through a very similar way, called the replacement process. This replacement process result in a remarkably similar deposits in terms of their mineralogy and the form of the specimens and crystals. For instance, a sample of CRD deposit found in China would have very similar mixture of minerals as it would in Mexico. The similarities in mineralization are so closely related that it helps create a geologic link between the deposits and highlights a clear proximity to large porphyry systems.
Core Assets Corp. and our Blue property, have been delivering preliminary results indicating that it could follow on the “Hub & Spoke” model similar to one of the largest CRD-Porphyry deposits in the world, Bingham Canyon as shown below:
“Hub & Spoke” as a reference model (On left); Blue Property potential model (on right)
Some of the discoveries based on the same model above are as follows:
Cinco de Mayo: Mag Silver
❖$2 Billion Market Cap
Taylor Deposit: Arizona Mining
❖ South 32 bought for $1.8 Billion
Resolution Copper: RC Consortium
❖ Estimated to produce 40 Boz Lbs of Cu over 40 years
Peñasquito: Newmont Goldcorp
❖ Fifth largest silver mine in the world (17.8 Moz Au + 1,070 Moz Ag
Why are CRDs important?
CRDs are the foundation of western civilization because of advancements in discoveries and usage. Also, they can be found in 10 to 150 million tons of very high grades economical elements. The low mining cost for CRDs and their metallurgically docile nature makes them increasingly important in today’s world. These deposits avoid big open pit mining leaving a minimal environmental footprint with very selective high grade underground mining.
Moving forward, industries would require a lot of these deposits to build new technologies and commodities. As a result, the growing demand for the minerals such as copper, zinc will help strengthen our economy.
If you’re interested in investing in CRDs, please visit our website at Core Assets Corp. (CSE:CC). We are focused on the development of their Blue Property deposit in Atlins, BC.
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The area of Stikine Terrain in British Columbia and the geological location of the most significant CRD projects and the large porphyry system.