Greek stocks headed north but in thin trade yesterday, leading analysts to argue that they have become too weak to follow the positive mood in foreign markets. The Athens Stock Exchange (ATHEX) general index closed 0.51 percent higher at 4,820.06 points. The FTSE/ATHEX 20 blue chip index gained 0.35 percent to close at 2,557.53 points after moving in positive territory throughout the session. The FTSE/ATHEX Mid-40 and the FTSE/ATHEX 80 small-cap index ended 0.52 percent and 0.61 percent higher respectively. Viohalco and Piraeus Bank were the only blue chips to add more than 1 percent. National Bank gained 0.92 and OTE 0.90 percent. Eurobank, Emporiki, Alpha Bank, Cosmote, OPAP and Titan also ended in positive territory. By contrast, Hellenic Technodomiki tumbled 3.64 percent while Bank of Cyprus was down 1.68 percent and Folli-Follie 1.63 percent. ATEbank, Postal Savings Bank, Public Power Corporation, Hellenic Petroleum, Intralot and Motor Oil were also leaner. Coca-Cola HBC was unchanged. Marfin Group hit the 20 percent limit up after successive limit downs last week. Turnover fell to a year low of -217.01 million, including -13.71 million in prearranged block trades. National Bank was the most marketable share with -18.1 million. Traders said the fall was partly due to the UK bank holiday.