Gold breached the Rs 12,000/10 gram mark in the spot Mumbai bullion market today on rupee depreciation and firm guidance from the global markets.Spot gold opened firm at Rs 12,010 per 10 gram - a gain of Rs 360 from the last close on Monday. The Mumbai market was closed yesterday.In the absence of buyers, gold was range-bound throughout the day, and closed around the same level today.Pure gold closed with a similar gain at Rs 12,060 per 10 gram as against Rs 11,700 per 10 gram on Monday.In Delhi, standard and pure gold closed with a gain of Rs 200 each at Rs 11,980 per 10 gram and Rs 12,040 per 10 gram today.