WESTERN Australian nickel companies Mincor Resources Ltd and Sally Malay Mining Ltd have joined newly listed Boart Longyear Ltd on the benchmark S&P/ASX 200 index at the expense of two other WA companies. These new entrants replace WA oil and gas explorer, ARC Energy Ltd, and diamond producer Kimberley Diamond Company NL. US-domiciled News Corp Ltd also returned to the indice after changes were made to the way companies are included in the S&P indices. News Corp and Boart Longyear also joined the S&P/ASX 100 index, at the expense of WA’s Iluka Resources Ltd, which remains in the S&P/ASX 200. The biggest change to the series is the inclusion of foreign-domiciled stocks on the core S&P/ASX suite of indices. Ratings agency Standard & Poor’s claimed the changes would result in a more fully diversified benchmark. S&P’s Australian director and head of index services, Jason Hill, said in a statement that the changes were done after a significant consultation. The index also launched its S&P/ASX All Australian 200, which excludes dual-listed companies. This index added Mincor, Sally Malay, Boart Longyear and Western Areas Ltd.