The upswing in merger and acquisition activity compared with a year ago suggests that a long period of low project valuations combined with strategic (or forced) portfolio divestitures is tempting buyers back into the market.

At the end of the first half of 2014, there were 56% more completed and pending metals and mining transactions than in the year-ago half, rising to 117 deals from 75 year-over-year.

However, the total price paid in the first half of 2014 was only 15% higher than a year earlier, and the value of all commodities acquired was 21% lower.

The average price paid per transaction was $US113 million ($A121.5 million), compared with $153 million in the first half of 2013, while the average value acquired per deal sank to $4.55 billion from $8.99 billion year over year.

There were four deals with prices of at least $1 billion in the half year, compared with three in the 2013 half, and 12 deals with values between $100 million and $999 million, compared with 14 in the prior year half.