LME three-month nickel is "looking frothy," says JP Morgan, noting a 50% increase in on-warrant stocks over the last month, "even if off a very low base." Highlights supply tightness with news of a possible 500 ton production shortfall from West Australia's Jubilee mine. Nickel looks set to retest the $48,500/ton highs, he says. LME nickel traded last up over 4% at $47,000/ton.