The New Zealand sharemarket started well and pushed on as world markets rallied and brokers talked of a building momentum.

The benchmark NZX-50 index closed up 30.789 points, or 0.953 per cent, at 3262.605 after opening up 11.66 points. The Australian market was up about 1.6 per cent as the local market closed.

"We have seen a very positive lead from offshore. The markets have had a good run over the last month or so and it is continuing into October," said Adrian Vance at Hamilton, Hindin, Greene.

"Investors traditionally view October as a tough month, which it can be historically, but we are getting some real momentum into these markets. It is really a momentum play that is at work here."

OceanaGold rose 23.17 per cent to 505 as the price of gold continued to trade at a record in US dollar terms. The company now sells its gold on the spot market.

The leaders featured among the gainers with Fletcher Building up 19c at 838 and Telecom up 6c at 208. Contact Energy rose 2c to 568.

TrustPower rose 5c to 735 and Auckland Airport rose 3c to 207.

New Zealand Farming Systems Uruguay fell 4c to 59 on a day it talked about lower milk production and the cost of disengaging with PGG Wrightson at its annual meeting.

Property trusts were weak as data continues to be mixed on the economy and the sector. AMP Office was down 2c at 78, Kiwi Income Property Trust eased 2c to 103 and Property for Industry fell 2c to 119.

Pike River Coal fell 1c to 119 and NZ Refining fell 5c to 365.

SkyCity rose 1c to 289 and Restaurant Brands rose 1c to 254. Mainfreight rose 4c to 699 and Nuplex rose 2c to 329.

In the United States, stock indexes hit their highest in five months as stronger-than-expected earnings and lingering US dollar weakness increased demand for equities.

The Dow Jones industrial average gained 0.7 per cent to 11,096.08, the Standard & Poor's 500 added 0.7 per cent to 1178.10, and the Nasdaq Composite Index rose 1 per cent to 2441.23.

About 9.1 billion shares traded on the New York Stock Exchange, the American Stock Exchange and the Nasdaq -- the highest day for volume since July 16, and above the year's average so far of about 8.77 billion.

- NZPA