Government policy touting encouragement for New Zealand's resource sector to underpin economic growth has taken an unusual turn, with the likelihood of increased taxes and royalty payments being imposed on mining companies.
The issue has not caused the crisis seen in Australia over increased taxes, but could not have come at a worse time for mining companies operating in New Zealand.
For the first time, environmentalists were invited to speak at the conference, while separate protesters briefly infiltrated proceedings and picketed the venue in small numbers.
More than 300 delegates heard from the country's two largest gold companies, Oceana Gold Corp and Newmont Waihi Gold, which outlined massive increases in costs, a predicament which state-owned enterprise Solid Energy, the country's largest coal miner, has been forced to deal with this week.
To some extent, the perception of rising production costs has been overshadowed by record or high commodity prices, but the reality is some of those prices have since weakened off alarmingly and been surpassed by skyrocketing production costs.
Solid Energy's quandary this week reflects first-hand what is happening both in New Zealand and Australia.
It is coming to terms with an expected $200 million revenue slump in the face of a 40% decline in hard-coking coal prices down to $US200 ($NZ248) per tonne.
Solid Energy's chief executive Dr Don Elder was scheduled as the first CEO to give a key, opening address at the conference, but was a disappointing no-show - everyone assuming he was dealing with the urgent operations review announced a fortnight earlier.
However, the day the conference ended, he announced Solid Energy was restructuring, with the loss of at least 140 jobs at Huntly, in Waikato, and a further 230 jobs in limbo at Spring Creek, near Greymouth, where the underground mine is under immediate suspension and faces possible mothballing or outright closure.
In Australia, thousands of jobs are at stake as the big mining companies begin consolidation in the face of declining Chinese demand, the most high-profile being BHP Billiton mothballing $US20 billion ($NZ24.9 billion) expansion plans at its Olympic Dam uranium and copper project.
Highlighting the problem and volatility, towards the end of this week spot iron ore prices fell almost 5% to $US90 per tonne causing stocks in Fortescue Metals Group, BHP and Rio Tinto to slump from between 2.5% to 4.8%.
Minister of Energy and Resources, Phil Heatley, made his first appearance at the conference and was taken to task at both a private meeting with mining company executives, and also publicly during question time.
Mr Heatley either has exceptional researchers and good memory, or appears genuinely well-versed in the sector.
However, unlike the previous two upbeat annual conferences when the pro-mining National-led Government was making and then attempting to fulfil promises and open up exploration, in Rotorua an air of confusion and uncertainty abounded.
Mr Heatley admitted to delegates there were "a lot of moving parts", which the Government was juggling, including a review of the Crown Minerals Act, review on fracking (hydraulic fracturing use in oil and gas production), Exclusive Economic Zone protections (passed into law this week on a 72-49 vote) and the Pike River inquiry.
"It [changes] may not be perfect for you, if decisions go against you," Mr Heatley cautioned the conference delegates.
His admission oil and gas royalties were "about right" and increases to the mining sector would be "conservative", later prompted informal, private, reassurances from government staff to some delegates that royalty increases would affect only new operators, as opposed to the established producers.
After effusively welcoming both domestic and foreign investment into the sector, Mr Heatley said the main concern for the Government was the health and safety of staff and the environmental impact: "Leave the place the way you found it".
Mining delegates hold a genuine concern that National's proposed changes to legislation may get through Parliament like a raft of recent legislation which has passed only by the narrowest of votes, 61-60, leaving the way clear for a new Government to easily overturn it.
Mr Heatley said he understood the resource sector was "edgy", given the jitters in offshore investment markets, and went on to claim to delegates that once legislation or amendments were passed they would be "locked in" to give "certainty" to companies and investors.
After his presentation, Mr Heatley said in a interview that while he had not spoken with Labour, that party had a better understanding of the resource sector, which offered jobs and growth, and claimed there would be "good across party support" for legislative change.
On the question of the growing public awareness and mistrust surrounding potential environmental impacts, Mr Heatley claimed the public "mood was shifting" towards acceptance.
"Taranaki oil and gas [exploration and production] can be repeated around the country," he said. As if on cue, two days later, the Ministry of Business, Innovation and Employment released an "occasional paper" looking at the benefits of having another offshore petroleum basin in development, saying exports could grow by $1.5 billion a year, royalty payments increase by $320 million and create a further 5500 jobs.
Government permitting agency New Zealand Petroleum and Minerals (formerly Crown Minerals) has boosted staff from six to 17 and is making inroads to clearing backlogs and reducing permit application times.
But compliance costs, both at central and local government levels, have been frustrating and expensive for many companies.
One explorer claimed 40% of every $1 million spent went on compliance, and Oceana Gold had to produce 35 reports to gain a 10-year mine-life extension.
At the forefront of ongoing legal challenges and, subsequently, more than six months of delays to starting production, is West Coast coal mine developer Bathurst Resources.
It has spent a total of $250 million to date on the West Coast acquisitions and development, and at present can only produce boutique quantities of coal.
Its plans to eventually mine up to 4 million tonnes of specialist hard-coking coal, mainly from the Denniston plateau above Westport.
It has become the focal point for Forest and Bird and environmentalists during the past year, since more than 20 council consents were issued a year ago.
While it is also exposed to global coking coal prices - like Solid Energy - Bathurst has initial process costs per tonne of $US115, falling over three years to $US85 per tonne.
Chief executive Hamish Bohannan was "pleased" to have won a High Court appeal a week ago when Forest and Bird was declined the right to have climate change issues heard in a forthcoming Environment Court hearing.
Despite legal delays, Bathurst has spent $8 million in exploration during the past year, with a further $36 million earmarked through to July next year, including Westport wharf upgrades.
For environmentalists, any euphoria on Solid Energy's likelihood of cutting back on coal production will be short-lived.
Dr Elder this week reiterated Solid Energy's commitment to further developing the use of Southland lignite - considered the most eco-unfriendly coal grade by environmentalists.
Dr Elder said commissioning of a $25 million lignite-to-briquette plant in Mataura would continue, as would conversion research of lignite to fertiliser (urea). The latter could displace imports and create an export market.
In considering raising taxes and royalties from mining companies, the Government has now opened another front of opposition, at a time it most needs that sector's support to underpin economic growth.
In 2010, New Zealand gold, silver and iron sand production was valued at $679 million.
The Government's endgame may well instead be eyeing a boost to the $2 billion in annual export receipts generated by the oil and gas sector - more lucrative than the onshore miners.
But battling on several fronts with environmentalists, the public and now miners, creates certainty for none.
