Two giant metal structures jut out from the sub-equatorial waters off the western Pacific island nation of Nauru. Now collapsed and abandoned, the former phosphate loading stations are evidence of a mining boom and economic downfall that saw one of the wealthiest nations in the world become one of the poorest in a generation.

At just 21 square kilometers, Nauru was once home to the purest phosphate reserves in the world. Nauru's phosphate -- created from the droppings of birds migrating across the ocean for thousands of years -- is a prized and essential ingredient in fertilizer.

In the mid-1970s when the country's economy peaked, Nauru's gross domestic product per capita was estimated at $50,000, second only to Saudi Arabia.

As the good times rolled, the government established the Nauru Phosphate Royalties Trust, a sovereign wealth fund that invested in international real estate. The country bought a fleet of Boeing 737 aircraft, public services were free and taxes virtually non-existent.

But by the turn of the century, the phosphate reserves were thought to have been exhausted and the nation's debts piled up. Most of the trust fund's assets were sold off and Nauru became increasingly dependent on foreign aid.

Australia, the country's most significant donor, now provides development assistance equivalent to roughly one-quarter of Nauru's GDP.

"We have eaten all the benefits of the land!" Julie Olsson, a local Nauruan, exclaims as she bounces around in her car while driving down the pothole-laden roads of the island's barren interior known to locals as "Topside."

Mining has rendered the inner 80 percent of Nauru uninhabitable, with the island's roughly 11,000-strong population almost entirely restricted to the coast. Now, the interior is dotted with jagged limestone pinnacles -- geological "leftovers" after the phosphate-rich soil was scooped out from the hard stone.

At 60 years of age, Olsson is acutely aware that her generation has reaped all the benefits of Nauru's wealth, leaving very little to pass on.

"We need to account for all the lost money. For our children to understand why we have such a big hole in the middle (of the island)," she says.

In 2005, the Nauruan government began "secondary mining" of phosphate left over from previous, less efficient excavation methods. However, even this economic lifeline is only generously estimated to provide an extra 30 years of revenue.

For Olsson, the "saddest" aspect of the economic downfall is the impact on her country's education system.

"(Previously) the government gave out scholarships to boarding schools in Australia. Virtually all of us, a big proportion of Nauruans, went to an Australian school," she said.

Olsson herself received a full scholarship to complete middle and senior school at a Christian girls' college in a rural part of Australia's eastern state of New South Wales, and credits her overseas education for her current work with non-governmental organizations.

"I love my culture and all these things, but I also understand that there is an outside world, and to be able to operate (on a global scale) we have to know the expectations and standards (of other countries)," she said.

In recent years, the Nauruan government, broke and devoid of other sources of income, has propped up its economy by hosting an offshore Australian immigration detention facility.

Asylum seekers who arrive illegally in Australia are transferred to the Nauru Regional Processing Center, where their claims for asylum are processed. The center consists of three separate facilities located at different sites on the island.

The Australian owned and operated holding facility is a key employer on Nauru, and generated A$115 million (about $82.6 million) in revenue for the island state in 2015-16, according to the Australian Department of Foreign Affairs and Trade.

However, both governments tightly control how much information about the camps is made public.

An A$8,000 non-refundable journalist visa application fee, introduced by the Nauruan government in 2014, has successfully deterred almost all foreign media from reporting from the island.

Days before international media were due to arrive in Nauru to cover the Pacific Islands Forum in September, one of the facilities named RPC-3, which accommodated families, single women and couples without children, was suddenly dismantled, with the inhabitants relocated into "settlements" in the community.

Among them are Mohammad, a 33-year-old Iranian who said that living conditions inside the tent camp were prison-like, with temperatures inside the tents sometimes rising to 50 degrees C in the equatorial heat.

Although most refugees and asylum seekers now live in the community, working in construction, barbershops or restaurants, everyone with whom Kyodo News spoke said not knowing where or when they will be permanently resettled is having a debilitating effect on their mental health.

A report released by the Refugee Council of Australia in September, coinciding with the Pacific Islands Forum, said children as young as 7 were attempting suicide, dousing themselves in gasoline and going into catatonic states.

"The problem is we have no hope, and as you know the humans are alive just because of hope," Mohammad said. "We are stuck between a rock and the ocean."

As of May, there are over 900 refugees and asylum seekers living in Nauru, the vast majority of whom have been recognized as genuine refugees.

While 164 refugees have been resettled in the United States since 2017, Canberra is yet to decide what will happen to those still on the island.

One refugee from Baghdad, who asked not to be named, said he came "from hell to hell," and no longer wanted to be resettled in Australia because of his experiences in Nauru.

"They treat us like animals," the 26-year-old said, referring to the Australian Border Force, the government body which overseas operations on Nauru.

With a general election in Australia to be held by May next year, it's possible that a new government in Canberra will end the highly-criticized offshore processing agreement, along with one of Nauru's most significant forms of income. In the meantime, all anyone can do is wait.