New Delhi, 25 March (NNS): The prices of big cardamom improved by Rs 20 to Rs 1670 per kg owing to the higher buying and higher import prices in Nepal. Recently, the prices have gone up by Rs 10 per kg. The average auction price reported to be around Rs 1400/1650 per kg in the last auction which held on 19th March. There is no possibility of more downtrend in the prices during the near future.