I can't tell if you honestly refuse to actually research what Australia passed, or you know and are just playing stupid and ignorant. Either way, I'll still explain.
Australia banned semi-automatic weapons (estimates put this up to 50% of the firearms in the country) In 1997. By banned, the government said that no one was allowed to possess such a firearm and made it a crime to do so. This was de facto confiscation since the government said turn over your weapons, or else. However there was a pesky law in their Constitution which said that the government cannot confiscate private property without compensation. To get around this, the government expanded the Medicare Levy Amendment Act of 1996 to include the money required to "compensate" the people for whom they were forcibly subjecting to confiscation.
Some estimates say they took 1/3 of all guns. Some have it higher at 1/2. The early dissenters were dealt with fast and harshly- they were imprisoned and warrants were issued to raid their homes and take any firearms found.
So yes, it was confiscation in every sense of the meaning.
As for your last comment- what exactly is supposed to be done about suicides? People have been killing themselves for well before a firearm existed. People still kill themselves by the hundreds of thousands in countries that have banned evil firearms.
As this chart shows, our suicide rate is no more troubling than countries like Norway, Switzerland, Sweden, Japan, etc. We have higher gross numbers because, wait for it- we have more people. And because the Chinese government does not count how many people commit suicide annually.