Materials stocks were up just 0.08% at midday Tuesday as the gold price hovered near the $4,000-per-ounce mark. On Wall Street, the tech-heavy Nasdaq index jumped 0.7%, while the S&P 500 rose 0.4%, both reaching record closing highs.

Rio Tinto (ASX:RIO) will invest AU$389 million, as part of a AU$733 million investment with Mitsui and Nippon Steel, for the development of the West Angelas sustaining project, part of the Robe River joint venture in Western Australia. The project seeks to develop new iron ore deposits in the West Angelas hub, and the deposits will maintain the hub's total annual production capacity of 35 million tonnes.

On the flip side, the communications services sector fell over 1%, leading to a broad-based decline.

Ovanti (ASX:OVT) said that 6 million fully-paid ordinary shares will be released from voluntary escrow on Oct. 14. As of Tuesday, the firm had 90 million shares subject to escrow restrictions. Holding locks applicable to the 6 million shares will be lifted before the start of trading on Oct. 14.