Harmony Gold Mining (HMY) had the highest return in Q1 2016 by a large-cap US stock, returning 246.7%.

ASSET	QUARTER	% RETURN
Harmony Gold Mining (HMY)	Q1 2016	246.68%
Coeur Mining (CDE)	Q1 2016	115.33%
Teck Resources Ltd Class B (TECK)	Q1 2016	107.92%
AngloGold Ashanti (AU)	Q1 2016	89.09%
Kinross Gold (KGC)	Q1 2016	83.78%
Equinox Gold (EQX)	Q1 2016	78.45%
Banco Bradesco S/A ADR (BBDO)	Q1 2016	68.66%
Pan American Silver (PAAS)	Q1 2016	63.2%
Banco Bradesco SA ADR (BBD)	Q1 2016	58.31%
Alamos Gold (AGI)	Q1 2016	57.44%
Freeport-McMoran Copper & Gold (FCX)	Q1 2016	56.67%
Gerdau SA ADR (GGB)	Q1 2016	53.44%
Ternium SA ADR (TX)	Q1 2016	49.09%
Allegheny Technologies (ATI)	Q1 2016	48.64%
ArcelorMittal SA ADR (MT)	Q1 2016	48.37%
Companhia de Saneamento Basico do Estado de Sao Paulo SABESP ADR (SBS)	Q1 2016	46.34%
Gold Fields Ltd ADR (GFI)	Q1 2016	44.82%
Telefonica Brasil SA ADR (VIV)	Q1 2016	44.39%
Newmont Goldcorp (NEM)	Q1 2016	44.28%
Hecla Mining (HL)	Q1 2016	44.21%
Super Micro Computer (SMCI)	Q1 2016	42.71%
Royal Gold (RGLD)	Q1 2016	40.04%
Itau Unibanco Banco (ITUB)	Q1 2016	39.01%
POSCO (PKX)	Q1 2016	37.63%
Credicorp (BAP)	Q1 2016	37.24%

Large-cap stocks are treated as having a market cap of $10B+.