|In 2004 Gemfields Resources PLC started systematic exploration south of the Ndola River, and made some important discoveries. Mining began in 2005. By 2007, Gemfields had acquired 100 percent ownership of two mines in the area.|
In June 2008, Gemfields formed a collaboration with the Zambian government, establishing a 75/25 ownership split of the Kagem emerald mine.
Cobbing is a very important step that removes highly included areas from the emerald rough.
Size classification is important since small stones are often less included than larger ones.