TOKYO, Apr 18 (Reuters) The Nikkei turned positive on Tuesday, rising 0.55 percent as investors bought shares in Nippon Mining Holdings Inc. and other resource-related firms after oil prices rose to near record highs.
Shares of Advantest Corp. fell 1.3 percent to 14,110 yen after brokerage Credit Suisse lowered its rating on the chip-equipment maker to ''neutral'' from ''outperform'' citing a likely fall in prices for its key devices.
U.S. oil futures cleared a barrel on Monday, nearly breaching an all-time high set in the days following Hurricane Katrina.
''I think a lot of this is probably speculative buying,'' said Yoku Ihara, manager at the investment information department of Retela Crea Securities, referring to the higher oil prices.
''I'm expecting that oil prices, at least in the short term, will climb higher,'' he said.
Higher oil prices -- which boost corporate costs and crimp consumer spending -- are a minus for most firms, but a boon for energy-related companies.
The Nikkei was up 92.66 points at 17,093.02 as of 0100 GMT, after earlier falling under the 17,000 mark for the first time since March 31.
The TOPIX index was up 0.57 percent at 1,728.86.
Shares in Nippon Mining Holdings, which owns Japan's fifth-largest oil refiner, rose 3.5 percent to 1,095 yen.
Oil developer Japan Petroleum Exploration Co. Ltd. gained 3.4 percent to 8,010 yen.
Shares of Canon Inc. declined, losing 1.2 percent to 8,150 yen.
REUTERS PDS PM0752