The following are the biggest percentage gainers on the TSX Venture Exchange in mid afternoon trading with their price movements PETROSHALE (PSH.V), $1.04, +0.50, +92.59% GREAT QUEST FERTILIZER (GQ.V), $0.20, +0.06, +48.15% ALLIANCEPHARMA (APA.V), $0.36, +0.11, +44.00% VIRIDIS ENERGY