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Jan 4 (Reuters) - Canada's main stock index rallied in the first trading session of the year on Monday, helped by gains in materials stocks, while upbeat factory data for December bolstered optimism around an economic recovery.
* The materials sector .GSPTTMT , which includes precious and base metals miners and fertilizer companies, added 4.2% as gold futures GCc1 rose 2.5% to $1,941.1 an ounce. GOL/ MET/L
* Canadian factory activity expanded at its fastest pace on record in December as new orders and production climbed, while manufacturers grew more optimistic that output would continue to rise in 2021, data showed. At 9:42 a.m. ET (1442 GMT), the Toronto Stock Exchange's S&P/TSX composite index .GSPTSE was up 112.3 points, or 0.64%, at 17,545.66.
* The largest percentage gainer on the TSX was Brookfield Property Partners LP BPY_u.TO , which jumped 16.5% after parent Brookfield Asset Management Inc BAMa.TO offered to take its real estate arm private in a $5.9 billion deal. Its gains were followed by SilverCrest Metals Inc SIL.TO , which rose 12.1% after the miner's Canadian subsidiary entered into a credit agreement with an affiliate of RK Mine Finance to provide a secured project financing facility for a total of US$120 million. The optimism in the Canadian market followed the upbeat mood in global markets as investors hoped the rollout of vaccines would ultimately lift a global economy decimated by the COVID-19 pandemic.
* The energy sector .SPTTEN climbed 1.6%, while the financials sector .SPTTFS slipped 0.2%. The industrials sector .GSPTTIN fell 0.1%.
* On the TSX, 151 issues were higher, while 66 issues declined for a 2.29-to-1 ratio favouring gainers, with 18.77 million shares traded.
* Ritchie Bros. Auctioneers Inc RBA.TO fell 2.9%, the most on the TSX, and the second-biggest decliner was e-commerce firm Shopify Inc SHOP.TO , down 2.7%.
* The most heavily traded shares by volume were Zenabis Global Inc ZENA.TO , Nevada Copper Corp NCU.TO , and Brookfield Property Partners LP BPY_u.TO .
* The TSX posted nine new 52-week highs and no new lows.
* Across all Canadian issues, there were 88 new 52-week highs and four new lows, with total volume of 52.69 million shares.