How many items are in The Crystal Caves collection?

There are more than 600 individual pieces in the collection.

How big are The Crystal Caves?

There are 300 m2 of tunnels and grottos for visitors to explore this unique collection of natural crystals, prehistoric fossils and other wonders of the world.

Who built them?

René Boissevain, who was introduced to fossicking for agates in dry riverbeds when he was a young man of 30. The agates, and the crystals within, became a passion.

How long did the caves take to build?

The first cave was built in 1987 using just René’s imagination – no architects, designers or builders. Five years later he decided to expand and make a series of caves and tunnels and chambers. This time he had a team of six including an engineer, electrician and carpenters. It was finished in 1992.

Why a cave?

René has always been a caveman – well a cave boy initially. As a child, instead of building tree houses or forts he dug out old rabbit burrows, and reinforced them with branches to make a cave. The lay of the land of the shop turned out to be a natural space to showcase his collection.

What’s in the caves?

A world class collection of crystals and fossils from round the world. Which you can touch! And you can take photos! Visitors can walk – and sometimes crawl around the web of spaces and discover the gems and stones for themselves.

When did René Boissevain start collecting?

Funnily, when René started his interest in rocks he thought an agate looked a little like a potato. It was 1963 and his first fossick was at Agate Creek, near Forsayth in NQ. After finding a hollow agate and the crystals inside, it was all on.

What is agate?

Agate is a banded form of finely-grained, microcrystalline quartz. No two are the same. Most agates occur as nodules in volcanic rocks or ancient lavas and are categorised as semi-precious gemstones. The bands or markings are made by a silica-rich liquid entering the cavity.

And there are things called a geode?

In some cases, the supply of silica-rich water runs out before the entire cavity or nodule fills in. When there is a hollow centre within a crystalline outer fill, the specimen is considered a geode.

What’s the most travelled specimen in the collection?

A 49kg Queensland agate nodule was unearthed in 1963 and was amongst the collection René took back to Holland in 1969 to help start a museum there. On returning to Queensland and starting his business in Atherton he pined for the big rock and in 2007 managed to convince the new owner of the Dutch museum to swap it for 49 kilos worth of smaller specimens. So, 44 years after it left Australia was returned home. The blue monster is also the largest agate René has uncovered.

Most impressive?

One of the largest amethyst geodes in the world. Standing at a staggering 3.27 metres, the geode weighs 2.5 tonne. Each of the thousands of perfect crystals was formed inside the geode exactly as visitors can see them now, 130 million years ago.

How did René get the collection?

Some he dug out of the ground, some he swapped for Australian agate and others required remarkable persistence. In one deal, it took three years for René to convince a Hong Kong trader to sell him an ancient Lapis Lazuli carving so rare the antiquities powerhouse (auction house), Sotheby’s couldn’t identify it.

Best prehistoric thing to have a crack at?

A geode called a Mexican coconut. The geodes are ancient crystalline formations that originated 44 million years ago during a volcanic eruption in Chihuahua. They look a bit like a coconut and you need a bit of power to open them, hence the name. Visitors are given gigantic cutters to do the honours. It’s a bit of a lucky dip, you never know what kind of crystals will be revealed.

Anything else of note?

Just 385-million-year-old marine fossils, the jawbone of an Ice Age woolly mammoth, dinosaur eggs from China and an agate that’s had the same water slopping round inside for 80 million years.