SHENZHEN had a break from B-share trading yesterday because of the holiday in Hong Kong to observe the Ching Ming Festival. B shares are traded by foreign investors, and most trades are conducted through Hong Kong. On Tuesday, the official Shenzhen B-share index fell 0.22 points to 73.97 points when market turnover was a mere HK$720,000. Players stayed away in anticipation of the holiday yesterday, although turnover is often so low that sellers have to lower prices to find buyers for their shares. The CLSA Shenzhen Index closed down 0.3 per cent. On Tuesday, port developers Shekou Port and Chiwan Wharf were at the centre of activity. Shekou fell 3.4 per cent to $4.20 and accounted for 58 per cent of trading. Chiwan fell 15 per cent. The CLSA Shenzhen A-share index fell 15.75 points to 1,071.2. On Monday, the Shenzhen CLSA B index rose 0.09 per cent to 771.98. China Southern Glass, China's largest manufacturer of high-grade process glass, fell 0.02 per cent to $4.55 after rising last week.