Toronto's main market was slightly lower Monday, amid investor caution as budget talks continue in the U.S. ahead of the looming fiscal cliff.

In corporate news,Telus Corp. Monday said Mason Capital Management borrowed or "otherwise acquired" shares at the end of November to “avoid publicly disclosing” a reduction in its shareholding of the company.

The company said that its foreign ownership level is “once again consistent” with the roughly 15% level it announced for mid-November.

But it noted that based on large reservation applications by non-Canadian investors, the telecom giant's potential foreign ownership level briefly spiked to more than 30% at the end of November, likely mainly attributable to Mason Capital. 

In metals and mining news, First Majestic Silver Corp. was down over 10% after it announced Monday that it is strengthening its presence in Mexico by acquiring Orko Silver Corp.  for $387 million.

Centamin plc  rose 14.55% after it early Monday said that the halt by customs on gold exports from its Sukari gold mine was lifted and a shipment was made yesterday. The company said fuel supply and normal operations at Sukari are expected to resume in the coming days, once payment for the latest shipment has been received.

Globex Mining  has obtained a final order from the Quebec Superior Court to spin out shares of its Chibougamau Independent Mines (CIM) subsidiary to its shareholders. Completion of the spin out is conditional on CIM closing its $10 million private placement financing first announced in October, which is being co-led by Casimir Capital and Marquest Capital Markets.

Shares in base metals producer Revett Minerals sunk more than 8% Monday after it temporarily suspended underground mining operations at its Troy mine in northwest Montana, citing concerns with geotechnical conditions.

The company said that while it believes conditions have stabilized, a decision was made to install geophone monitoring devices and to begin recording and analyzing data in the coming days.

Turning to the junior resource sector, African Queen Mines  Monday said it would end development at its King Solomon Project in Mozambique to focus on projects in Kenya and Ghana.

The company said it made the decision after "a thorough review of its portfolio of exploration properties" in Southern, West and East Africa, in order to reduce costs of operations and to prioritize projects for development in 2013.

Cadillac Ventures  has recently turned its focus to the former Burnt Hill tungsten mine in New Brunswick – a property on which the company expects to restart development for little cost.

Late in November, the Toronto-based company announced that it resumed exploration on the property, which covers more than 125 square kilometres and has NI 43-101 compliant tungsten, tin and molybdenum resources.

Vancouver-based Sunridge Gold says that talks are progressing with the Eritrean National Mining Corp (ENAMCO) for the African company to buy a 30% participating interest in the gold explorer's Asmara project in the region.

The Canadian junior gold company said that negotiations are progressing within the framework of the mining code of the country.

The price and terms for the participating 30% stake are still being negotiated.

Bayfield Ventures  has closed the non-brokered private placement financing it announced last month, raising $1.4 million for its drill program at the Rainy River gold properties in northwestern Ontario.

PacificOre Mining Corp  has received the results of a recent surface geophysical survey over its Lac Dore vanadium-iron-titanium deposit in Quebec, confirming the presence of a significant magnetic anomaly.

The magnetometric survey, carried out by Geosig, confirmed a 2.6 km long and 200 metre wide magnetic anomaly, which corresponds to the main Lac Dore iron-titanium-vanadium deposit - the object of SNC Lavalin's 2002 resource estimate.

Shares in Colt Resources  jumped Monday after the company announced final drill results on its Banhos gold deposit, part of the Boa Fe gold project in southern Portugal.

Notable holes included 8.39 grams per tonne (g/t) of gold over 6.88 metres and 33.2 g/t gold over 1.7 metres.

Shares in Bralorne Gold Mines were lately changing hands 12 cents higher on Monday, after announcing high grade gold drill results at its Bralorne mining operation near Gold Bridge, British Columbia.

High grade results announced in October were confirmed by a second assay Monday, as 409.5 grams per tonne (g/t) of gold uncut were intersected over a 2.1 metre core interval.

Meanwhile, another gold-bearing quartz vein intersected in the same drill hole returned 25.0 g/t gold uncut over a 0.6 metre core interval. Together with adjacent mineralized rock, the weight average assay is 11.8 g/t gold uncut over a 1.9 metre core interval.