After spiking on the first day of trading last week, shares in Pike River Coal have dropped further below their issue price as the coal mine's largest owner pledged more capital.
Shares in the West Coast coal mine debuted on Friday as high as $1.08 and finished theday at $1.03 - up 3c on the $1 issue price.
But by yesterday they had fallen to 95c.
ASB Securities adviser Stephen Wright said the rise in the New Zealand dollar over the past couple of days was likely concerning investors.
But some investors had also probably decided to sell out after the stock rose only modestly on debut, he said.
"All these stocks, once they lose a bit of momentum, people just give up on them and the marginal investor just exits it," he said.
"There's just not enough demand coming through and the price will keep drifting down."
The fall came despite Australia's second largest coal company, Centennial Coal, saying on Monday that it believed strong coal prices were not a short-term phenomenon and the outlook remained good.
Last week Pike River said the $65 million float had been oversubscribed and an extra $20 million worth of shares had been issued.
New Zealand Oil & Gas, which spun off Pike River into a separate company for the initial public offering and remains the largest shareholder with 31 per cent, yesterday promised $25 million more capital beyond next January should Pike River need it.
The company "reaffirms its commitment to Pike River to ensure it realises its full value by completing the development of the Pike River Mine and achieving coal production on schedule".
The company also "agreed that ... upon request of Pike River, it will provide equity funding or other financial support of up to $25 million to [Pike River] on usual and reasonable arm's length terms and conditions to be agreed."
The mine's first coal production was expected in the first quarter of next year.
