Collecting Unusual Rocks and Minerals for Kids and Adults
Looking for some unusual rocks, fossils, gemstones and minerals to collect? Here are 10 odd specimens that appeal to amateur rockhounds of all ages! Be the envy of other mineral collectors with strange stones that have special stories and are surefire crowd-pleasers.
Rocks and minerals are a great way to share a hobby and learn about geology. You can find most of the ones on this list at lapidary and rock shows or even fossicking, if mum or dad are keen! Many of these specimens are relatively inexpensive, so you won’t have to break the bank in order to start a really cool beginner collection.
1. Magnetite Crystals on Hematite Magnet
This is a new addition to my own collection, as I couldn’t resist it at the most recent lapidary show I attended. Basically it is a hematite stone that has been turned into magnet and had magnetite crystals sprinkled all over it.
Magnetite and hematite are both iron ores. Magnetite is the most magnetic mineral in the world and when it was discovered, it was used in the world's first magnetic compass. Magnetite is mined in the USA and Canada.
Hematite is made up of 70% iron and is found in Brazil, Australia and Asia. It is far easier to mine than magnetite, because it already contains a lot of iron, so it doesn't cost as much to extract the iron for commercial use.
You can pull the magnetite off and put it on again, just like playing with magnets, only it’s more geological looking.
2. Dinosaur Poo (Coprolite)
Ahhh, the joys of owning your very own piece of fossilised dinosaur poo! If you don’t already have a specimen of this interesting stone, then try to get one, because it’s so realistic looking and can almost be mistaken for the real thing, although it’s a lot friendlier.
Fossilised animal dung is known as coprolite and palaeontologists break open coprolites to find out about the diet of the animal. Sometimes, bones, teeth or scales can be discovered inside and the shape can help them understand the type of body it came from. Coprolites can be found in many parts of the world and the smallest ones look like pellets or tiny eggs.
3. Television Stone (Ulexite)
Ulexite is also known as TV Rock, TV Stone or Television Stone, because of its amazing fiber optic properties. When you put a piece of newspaper underneath it, you can see the contents of the paper appearing on the top of the stone. The fibres in the rock act like the fibre optic cables of a television, transmitting light from one surface to another.
Another special effect of ulexite is that when it is held up to a light or has a laser shining through it, it will produce concentric circles of light. Ulexite is a boron ore and can be found in the deserts of southwest America, Turkey and Chile.
A good quality piece of ulexite needs to be polished at a perpendicular angle to the fibers to produce this effect, so test ulexite specimens before buying them to make sure they display the correct optical properties.
4. Fool’s Gold (Iron Pyrite)
Iron Pyrite is a delight for kids because it reminds them of real gold. It is often found in quartz veins near gold and can be mistaken for such, so that’s why it is also called “fool’s gold”. You can also find it in sedimentary rock, metamorphic rock, in coal beds and in some fossils.
Pyrite is the most common of the sulfide minerals and can make sparks when struck against steel. It is also used in marcasite jewellery, which was popular during the Victorian era. Today it is mined for sulfur dioxide and is used in batteries and radios for conductivity.
A good specimen of pyrite has a cubic crystalline structure and it is a common mineral that is found in abundance around the world.
Ammonites are the fossils of prehistoric sea creatures that were able to swim in prehistoric oceans using little tentacles. There are hundreds of ammonite species around the world and the most popular ones are from Morocco, where the Sahara desert was once covered by a vast ocean millions of years ago.
Ammonites died out out about 65 million years ago, along with the dinosaurs and scientist like to use them as index fossils to determine geological time periods based on species. They look good in rock collections because they can contain all sorts of minerals from hematite to agate, pyrite to crystal.
Usually ammonites are cut in half and polished to show off any internal chambers filled with gemstone. Lesser quality specimens are left whole, as there is no gemstone contained within.
6. Rutilated Quartz
Rutilated quartz (also called sagenite) is quartz with rutile in it. Rutile is a small, needle like crystal that can be golden, black, silver, green or red.
The most popular is the golden rutilated quartz, which is also known as “Venus hair stone” because the rutile looks like little golden hairs.
Rutilated quartz comes from Kazakhstan, Australia, Brazil, Norway, Madagascar and the USA. It is a rare stone that is hard to find and the rutile is made up of titanium dioxide.
Lots of people like collecting rutilated quartz but it is not used much in jewellery because it is a softer stone that can be scratched easily.
7. Thunder Eggs
Thunder eggs or thundereggs are egg shaped and when you cut them in half, they often contain agate, jasper or opal. They are made from a special formulation of prehistoric volcanic lava and can have other minerals and crystals in them too.
They are different to geodes, because geodes are hollow while containing crystals, whereas a thunder egg is mostly filled with minerals and the name comes from Native American folklore where it is said that they are the eggs of thunderbirds, who threw them at each other.
Thunder eggs vary in size and can be a few centimetres wide to bigger than a tennis ball. They can be found all around the world, but are especially known in the USA, Germany, Africa, Poland, Australia, Romania, Turkey, Mexico, Argentina, Canada and France.
8. Meteorites (Tektites)
Tektites are made of terrestrial (or alien) rocks and are thought to be created by meteorites which hit the Earth’s surface and drop molten bits of rock off. They are irregularly shaped and are usually a glassy type of rock in a dark colour, sometimes transparent.
Tektites are the driest known minerals on Earth, containing 0.005% water content. They can be found only in certain parts of the world, spread over large “strewn fields” and the three major areas are Southeast Asia (especially Thailand and the Philippines), Australia, North America (Caribbean) and West Africa (The Ivory Coast).
Some tektites are called moldavites and these ones are green and transparent when held up to the light. Moldavites are found in Moldavia in former Czechoslovakia and are believed to have come from a meteorite crater in Germany. Fine quality moldavites are used in jewellery to display their naturally unusual shape.
Trilobites (or trilobytes) are extinct marine creatures that have fossilised from millions of years ago. They are arthropods and filled the oceans for over 270 million years, which makes them quite common. There were over 17,000 species of trilobite and it is believed they died out due to lowering sea levels and less food diversity available.
Many lived on the sea bed, scavenging and feeding, while others swam and ate plankton. Trilobites can often in be found with other salt water marine fossils and geologists use them to date the age of the rocks where they are found (by knowing the different time periods in which various trilobite species existed).
Every continent in the world has trilobite fossils and some trilobite fossils show an outline or imprint only, while others preserve the whole skeleton.
Geodes are great for children’s rock collections, because they are very appealing! They are basaltic lava or limestone rocks that are hollowed out and contain crystals. The crystals can be one of many different types, although quartz is the most common one to be found in geodes.
Some geodes can have agate, chalcedony or jasper on the edges of them. When geodes are cut in half and polished, they make great ornaments for the home.
Geodes can be found in many places around the world, but there are well known geode areas in the USA (Indiana, Missouri, Iowa, Kentucky and Utah) and in Brazil, Namibia and Mexico.
Which one do you like the most?
If you’ve already collected most of these and are looking for further specimens to discover, try these affordable gemstones:
- Moss Agate
- Picture Jasper
- Boulder Opal
- Agatised Rhyolite
- Fossilised Nautilus
- Fossilised Sea Urchin
- Shaman Stone
- Baryte Rose
- Tiger Eye (or Cat’s Eye)
- Fossilised Shark Teeth
- Moon Rock*
- Peacock Ore
*Moon Rock will put a bit of a dent in your budget, as it is priced per gram and is considered rare, since it is brought back to Earth by astronauts.
© 2014 Suzanne Day