J-Block was originally developed by GS Esterhuizen during 1995-1996 to evaluate the probability of block instability in the tabular stopes of the South African platinum and chrome mines. Inputs and concepts during the development of the software came from TJ Kotze of SAMANCOR, B Streuders of Eastern Chrome Mines, W Joughin of SRK Consulting South Africa as well as the many users of the software over the years. JBlock is still mainly used in South Africa where it is most applicable, with a few users in Australia, Chile and Canada.

S-Block is an adaptation of J-Block for analyzing open mine bench stability. This software was developed by GS Esterhuizen during 2001-2002 to fill the need for a method of assessing bench stability in open pit mines. The first application of the program was in 2003 with E Hamman of AngloGold to evaluate bench stability at a Colorado gold mine. Since that time SBlock has found application by practicing rock engineers in all the major mining countries of the world.