Thundereggs & Spherulitic Rhyolite (Rainforest Jasper)

Mt. Hay is the remains of an extinct ancient volcano, which was last active about 120 million years ago. When it was a rumbling volcano millions of gas bubbles were present in the molten rhyolite lava .. it is these gas ‘pockets’ that became thundereggs. Thundereggs or volcanic birthstones are the result of these “pockets” filling with siliceous liquids containing impurities and trace elements, which crystallize as they cool, and when cut in half, reveal many different colours and patterns.

Fossicking  –  (9:00am – 4:30pm)

Visitors can fossick through piles of thunderegg – bearing material which is excavated from the nearby mine site, and transported to a safe area suitable for all ages. Visitors are given a bag for their stones, a tool to fossick, and shown what to look for. Any stones collected can be kept, and upon completion of their search, each person can have a couple of stones cut for free. Extra cutting is available at extra cost. Fees apply for fossicking, and enclosed footwear is required. No fixed starting times or bookings required but we suggest arriving by 2pm at the latest to enjoy the full fossicking experience. Our hours of operation are 7 days a week, 9am to 4:30pm. Pets allowed if kept under control.


Adults: $30

Seniors: $27

Kids (5-17): $15

Under 5s: $5

Family Rate (2+2 or more) – 10% off total price

We are open 7 days a week – 9am to 4:30pm

We also cater for Student Groups! Email us for more info. Bookings are required. 


Gift Shop

Also on site is a gift shop with an extensive range of gemstone and pewter products, including souvenirs, gifts, gemstone jewellery, carvings etc. and “Aradon Fine Pewter” products, which are manufactured on site.

The kiosk sells cold drinks and ice creams. Visitors are encouraged to bring their own lunch. Open 7 days a week, 9:00am to 4:30pm.


Mount Hay Camping

Powered Site: 2 adults/1night $25 – $5 each additional person

Unpowered Site: 2 adults/1night $20 – $5 each additional person

Pets allowed (must be controlled)
Camp Fires are allowed
Basic Hot showers
Coin-operated Washing Machine


Hear what a Mt Hay experience is all about..!

Wow! What a fabulous experience. Our plan was to stay for only 2 nights but we stayed for 4 instead. We thoroughly enjoyed our visit. The rocks and particularly the Thunder eggs are so cool! This a great place to go whether for a day visit or overnight. There is something there for all ages. Don and Roi were great hosts, very knowledgeable and helpful and passionate about what they do. Friends came up and joined us one day and said “What a hidden Gem of a place.” We can’t wait to go back again!????

- Merrilee

This doesn’t look like your average ‘tourist attraction’. It is very low key. But what it lacks in flash is made up for in the literally hands on access you are given to the rocks and the gems on hand. If you choose to fossick for your own thunder rocks (I did) you are shown what to look for and then handed a pick and a pail of water to find your own. It didn’t take long. I brought in a handful of stones and watched as they were cut open in the workshop. I loved it! Hands on discovery adventure with no hype or false promises.
If you don’t want to fossick, there are open displays of all sorts of gems and rock samples, both polished and unpolished sitting on the shelves in the shed and outside in the rock garden.
This is a great place to bring curious kids of all ages.
I camped there overnight. Again, nothing flash in the facilities, but they were all clean and worked well. I’d do this again in a heartbeat.

- Judy

What a great place to visit and fossick for Thunder eggs. Plain rocks can have the most beautiful colours inside. You can read about how they form and look at examples. There is a great gift shop with rocks starting as low as a few dollars, catering for every budget. The fossicking was great – a very short, assessible walk from the gift shop and you get instructions on what to look for. In an hour we got lots of interesting rocks and they cut a couple for us, included in the price, which was very exciting. A great day out or just spend an hour. There are also a limited number of powered and unpowered sites if you want to stay.

- Carolyn