The desecration of an Aboriginal sacred site in the Northern Territory is a loss of heritage for all Australians, a magistrate says.

Magistrate Sue Oliver on Friday found that OM (Manganese) Ltd damaged and desecrated a sacred site known in English as Two Women Sitting Down, at Bootu Creek, about 170km north of Tennant Creek.

This is the first desecration conviction in Australia.

The company blasted and mined 40 metres away from the site, causing it to collapse in 2011.

“What has been there for many thousands of years has been lost forever,” Ms Oliver said.

“It’s not just a loss for traditional owners, it’s a genuine loss of heritage for the country.”

To the Kunapa people, the site relates to a dreaming story about a marsupial rat and a bandicoot that had a fight over bush tucker.

The blood from the creatures spilled out onto the rocks, turning them a dark red colour associated with manganese.

Community representative Gina Smith said the site was part of a dreaming songline. Like a railway line, each sacred site represents a station along the way.

“I can’t take our children there to teach them the law. There’s nothing there to see now,” Ms Smith told reporters in Darwin.

Ms Oliver said the community felt the loss of the site in a direct physical sense and believed that as a result people had become sick and died.

“It’s like losing your mother… we believe the country does send warnings,” Ms Smith said.

The subsidiary of Singapore-based OM Holdings Ltd has been fined $150,000, substantially less than the $400,000 maximum penalty.

“The defendant did not consider damage to the site as a vague and remote possibility,” Ms Oliver said, and any claims that it had not foreseen the work would interfere with the site’s sacredness amounted to “wilful blindness”.

Artist Banduk Marika, board member of the Aboriginal Elders Protection Authority, said OMM got off too lightly.

“You go to a cathedral overseas and start desecrating it, you’re putting yourself in big trouble,” she said.

“Is this a reasonable fine? I don’t think so.”

The fine is not paid to compensate the traditional custodians of desecrated land, but to the NT government, something Ms Marika said needed to change.

“It’s not all about money,” Ms Smith said.

“We want to have something to show our kids, not just land ripped up.”

OMM presented a mining plan they knew posed a risk to the site, including the potential for destruction by blasting to obtain a steeper angle and obtain more ore, Ms Oliver ruled.

“The defendant company made decisions that favoured business and profit over the obligations they had (to protect the site),” she said.

OMM CEO Peter Toth said the company never intended to harm or disrespect the site.

“We sincerely regret the damage and the hurt caused and I unreservedly apologise to the site’s custodians and traditional owners,” he said in a statement.

NT Minister for Regional Development Alison Anderson said the ruling made clear that indigenous peoples are active stakeholders in the welfare of the sacred sites and should be treated as such, rather than passive beneficiaries.

“We recognise that mistakes can be made, but this decision says we are all accountable for these mistakes and a mistake that affects indigenous culture is no less serious than one that affects white-fella law,” she said.