Prices of mustard rose marginally in Jaipur as arrivals of the oilseed in local markets declined amid higher crushing activity by mills. However, futures contracts of mustard declined as traders booked profits after the May contract hit a two-week high. The most active June contract slipped a tad to 3,901 rupees per 100 kg while the May contract was down 7 rupees at 3,862 rupees.