Liberian newspaper Heritage in May reported that Liberian diamond mining company Youssef Diamond Mining Company (YDMC) had announced the discovery of what could turn out to be the largest diamond field in West Africa.

Responsible for the discovery of Liberia’s kimberlite dike deposits was South African-born geologist Steve Haggerty, YDMC chief geologist.  

Speaking to Mining Weekly in August, YMDC CEO Roger Youssef explained that a diamond-bearing kimberlite pipe 2.5 ha in area, along with five dikes 10 m in width and 50 m to 100 m in length were discovered at Camp Alpha in north-western Liberia by YMDC.

“The area has been worked sporadically for the past 75 years by local, small-scale alluvial miners and explored by several mining companies, but the diamond source was never found,” Youssef said.

Haggerty added that work undertaken this year had led to the discovery of two new kimberlite pipes based on the exotic botanical indicator Pandanus candelabrum.

He said the pipes are relatively small (50 m x 15 m), but that both have positive kimberlitic indicator minerals.

Another five potential pipes were indicated following advanced spaceborne thermal emission and reflection radiometer (Aster) satellite images, one of which was similar in its signature, but substantially larger than the pipe at Camp Alpha, Haggerty pointed out.

He noted that, in addition to these, transported ilmenite with distinctive chemical compositions indicated that another kimberlite cluster was present to the north of the Camp Alpha discovery.

Youssef and Haggerty said the Camp Alpha kimberlite cluster was one of many in the 500 km2 tenement.

Given the long history of alluvial diamond recoveries, in the range 50 ct to 450 ct, they said they were confident that several mines could be developed in the primary kimberlite.

All indications are that the large diamonds are Type II diamonds comparable to those found in neighbouring Sierra Leone and mined at Karowe, in Botswana, and Letšeng, in Lesotho. All are from small diameter pipes of comparable geological age.

Mechanised alluvial mining in the Gbeya river that transgresses the YDMC property is also planned.

These will be the first large-scale diamond mining operations in the country, with clear economic benefits to the government and the people of Liberia, Haggerty and Youssef acclaimed.

They noted, however, that work in the region had not been without its challenges, with thick bush, poorly maintained laterite roads and log bridges, porous boundaries, smuggling, illegal mining and globally recognised corruption highlighted as considerable ones.

Moreover, financial support was limited during the earlier Ebola crisis and the current Covid-19 pandemic, but with advanced discoveries, Youssef and Haggerty are confident that Liberian diamonds have a bright future in the global market.

“With the closing of mines and no new finds over the past decade, it’s possible that West Africa may return to the production figures of the 1970s when it produced 10% of world’s diamonds exclusively by small-scale artisanal alluvial mining,” they enthused.

YMDC said its field activities closed at the end of July with the onset of the monsoon season, but laboratory studies and analysis would continue at Florida International University, in Miami, in the US, under the direction of Haggerty.

Although the company’s focus in the region is on diamonds, YMDC is also interested in, and is licensed to explore for gold, base metals and coltan.