The new year celebrations this year may have been a bit lackluster for some of our readers, but for one mine in Angola, it was quite sparkly. The Lucapa Diamond Company Limited announced with its partners Empresa Nacional de Diamantes E.P. and Rosas & Petalas the recovery of a 113 carat gem-quality white stone diamond by Sociedade Mineria Do Lulo (“SML”) from its Lulo alluvial mine in Angola.
The company said that it is particularly significant, as it shows that these large and high-value diamonds continue to occur right up to the current focus area of their kimberlite exploration program.
Natural diamonds, both gem and industrial quality, are the product of either open pit or underground mining, in which diamonds are contained in kimberlite pipes, or they are extracted from alluvial deposits in riverbeds, coastal, and undersea locations. Each scenario requires an efficient and streamlined mining process to recover the most diamonds in the most economical way. (If you want to know more about the geology of kimberlites and diamonds, GIA, one of the world’s foremost authority on diamonds, colored stones, and pearls, has a published an in-depth article about Kimberlites: Earth’s Diamond Delivery System.)
Miners determine if a kimberlite pipe is worth pursuing by conducting regional sampling schemes and airborne geophysical surveys in a precise search area. Once a list of the best targets is assembled, grade analysis is done to find out if the kimberlite is sufficiently diamondiferous. Mining geologists can perform ore grade control with portable XRF analyzers to figure out where the most profitable ore bodies are, in terms of location and mineral concentration variability. Portable XRF analyzers can provide accurate sample data analysis for mining and exploration applications, including grade control, mine mapping, and identifying drill targets.
If you’ve read the Advancing Mining post, The Diamond Shortage: The Hunt for Kimberlite and New High Quality Synthetics, you can appreciate how rare it is to find a diamond, never mind one of such significant value. As we mentioned, most diamonds are found in kimberlite pipes, and few pipes yield enough diamonds to be worth the effort of mining them.
I bet the Lucapa Diamond Company is probably thinking it was definitely worth the effort.