Regnis (Lanka), another stock which has drawn speculators, closed at 488.80 rupees, up 68.50 rupees. The main All Share Price Index was unchanged at 6,783.39, while the more liquid Milanka index fell 0.22 percent (13.14 points) to close at 6,031.97, according to stock exchange figures.
Turnover was 2.1 billion rupees.
Colombo Dockyard, which stands to benifit directly from offshore oil and gas exploration and production as it builds support vessels, closed at 259 rupees, down 1.
20. There was a crossing of 96,000 shares at 260 rupees each.
Hemas Holdings, which has a stake in ship owner Mercantile Shipping and has said it wants to expand its maritime business, closed at 39 rupees, up a rupee in thin trade.
Cairn India said Sunday it has made a natural gas strike off north-west Sri Lanka, in the Mannar Basin with its first test well that was started in August.
Brokers said Colombo's stock prices were already seen as high, having risen to record highs and the bourse one of the world's best performing since the 30-year ethnic war ended in 2009.
Index heavyweight John Keells Holdings closed at 203.
90 rupees, down 1.10, with a crossing of 430,000 shares at 205.
50.
Asian Alliance Insurance, on which a 10 percent price band was slapped last week after its price shot up, closed at 380.
90 rupees, up 30.30, with 598,300 shares done. It hit a day's high of 394.30 rupees.
There was a crossing or off-market private deal of 100,000 shares of Asian Alliance Insurance at 360 rupees.
Blue Diamonds Jewellery Worldwide non-voting shares were the most actively traded stocks, closing at 4.
70 rupees, down 10 cents, with 2.4 million shares traded.
Ascot Holdings was also heavily traded, closing at 180.
80 rupees, down 8.10, with just over million shares changing hands.
Colonial Motors accounted for the highest turnover of the day, closing at 491.80 rupees, up 16.90 rupees.
There were two crossings, one of 278,300 shares and the other of 121,700 shares, both at 480 rupees a share.