Mumbai, Oct 18- Benchmark Nifty retreated from record highs to end at 10,210.85 today on the last session of Samvat year 2073. The BSE benchmark Sensex too fell by about 25 points to close at 32,584.35. The 50-share Nifty fell by 23.60 points or 0.23 per cent to close at 10,210.85 after moving between 10,175.75 and 10,236.45. The Sensex resumed lower at 32,518.56 and fell further to a low of 32,462.85 before ending at 32,584.35, down 24.81 points or 0.08 per cent. The Sensex had shed 24.48 points in yesterday's trade. The BSE and NSE will conduct a special Muhurat trading session tomorrow between 1830 hrs and 1930 hrs on the occasion of Diwali.