Aug 17 (Reuters) - Canada's main stock index rose on Monday, boosted by shares of precious metal miners, as China rolled out more stimulus to support the world's second-largest economy during the COVID-19 pandemic.

* China's central bank on Monday rolled over maturing medium-term loans while keeping borrowing costs unchanged for the fourth straight month.

* The materials sector, which includes precious and base metals miners, surged 4% on higher gold prices.

* Gold consolidated near the $1,950 mark after plunging 4.5% last week, supported by a weaker dollar as investors await the fine print on the U.S. Federal Reserve's strategy to stem the economic toll of the coronavirus.

* The largest percentage gainer on the TSX was Barrick Gold , which jumped 10.1%, as Berkshire Hathaway Inc disclosed investment worth $563.6 mln in the miner.

* At 9:48 a.m. ET (1348 GMT), the Toronto Stock Exchange's S&P/TSX composite index was up 121.96 points, or 0.74%, at 16,636.57.

* The energy sector was flat. U.S. crude prices were up 0.4% a barrel, while Brent crude added 0.1%.

* On the TSX, 141 issues were higher, while 74 issues declined for a 1.91-to-1 ratio favouring gainers, with 20.19 million shares traded.

* Cineplex Inc fell 2.4%, the most on the TSX, after CIBC cut its target price on the entertainment and media company. The second biggest decliner was oil and gas producer Enerplus Corp, down 1.8%.

* The most heavily traded shares by volume were StageZero Life Sciences Ltd, D-Box Technologies Inc and Zenabis Global Inc.

* The TSX posted eight new 52-week highs and no new low.

* Across all Canadian issues there were 19 new 52-week highs and four new lows, with total volume of 54.37 million shares.

(Reporting by Shivani Kumaresan in Bengaluru; Editing by Amy Caren Daniel)