Australia shares seen steady; commodities stocks on radar

SYDNEY, July 21 (Reuters) - Australian shares are poised for a steady start on Tuesday, tracking a muted Wall Street, but a plunge in gold and metal prices is likely to weigh on commodities-related shares. Investors will also be on the sidelines ahead of the central bank's minutes of policy meeting due at 1130 a.m. local time (0130 GMT). Local share price index futures rose 0.2 percent overnight, to sit at a near 35-point discount to the underlying S&P/ASX 200 index. The benchmark rose 1