New Delhi, 19 October (NNS): The prices of black pepper Markara remained firm at Rs 655 per kg owing to the sluggish trend in its sale and recent downtrend in the temperature. Recently, the prices have improved by Rs 10 per kg. The arrivals reported to be negligible in Kochi and the prices remained firm at the level of the previous day. The spot black pepper prices will likely to remain sluggish during the coming days.