CANADA STOCKS-TSX down as as energy, gold mining stocks weigh

* TSX down 29.59 points, or 0.19 percent, at 15,596.14 * Materials and energy losses offset smaller gains elsewhere * Suncor, Canadian Natural slip with oil price (Adds strategist comment, details, updates prices) By Alastair Sharp TORONTO, Sept 2 (Reuters) - Canada's main stock index slipped on Tuesday as falling oil and gold prices hurt the shares of energy companies and gold miners. The retreat comes in the broader context of an ascendant index hitting fresh record high