Boulder Opal is a unique and beautiful opal found in
Queensland, Australia. It is easily identifiable because it is a mixture of
ironstone and opal either in a matrix or layered. Every stone is unique and
they are arguably the most affordable opal available.
This unique opal is spread over thousands miles and known as
the Winton Formation, which is millions years old. Famous Boulder opal fields
include Winton, Quilpie, Opal town, Jundah, Bulgaroo and Kyabra .
Koroit and Yowah are two opal fields close together and are
now producing popular opal that has more pattern and unique style more than
colour as most boulder opal fields.
We have now added these fields under Boulder opal as, many
new buyers miss these categories. They have reputation for veins of colour in
spectacular patterns compared to other Boulder opals fields
Koroit and Yowah generally have more dark chocolate
ironstone backing and other opals fields have more sandstone light brown colour
and both can display veins caramel colour.
Boulder opals have more variety and uniqueness compared to
other opals and gemstones as so many factors have taking place over million
years and different mineralization has helped in huge cross spectrum of unique
boulder opals that you can enjoy
Another interesting type of Boulder Opal is the wood
replacement fossil. These stones have replaced a cavity left over by old wood.
This creates a stone with a unique wood pattern. Check them out, they are
amazing.
Please note some colour bars on this opal is very thin and
sometimes buyers mistake for doublet which is man made by joining crystal opal
to ironstone
To check that it is genuine opal, best to have magnifying
glass and view colour bar and you can see it isn’t glued by following colour
veins. Also you may place in freezer for few minutes and if a doublet the glue
would crystalize and easy to see
It is an extremely stable type of opal that does not
generally crack or craze. Since it is mixed with ironstone it is very strong
and resistant to breaking, but some boulder opals do show crack lines and most
of these are caused when the opal was formed a s many times you will split open
a boulder opal to see crack lines which could have been caused by shifts in the
earth to earthquakes or movements when the opal was forming.
We have a large range of polished stones that are suitable
for placing into jewelry. Most of our verified sellers cut and polish their own
stones.
There are also some very unique carvings available for sale.
The ironstone matrix is a perfect medium to carve interesting shapes while
trying to follow the color bar They make great gifts and they are so unique.
延伸阅读
![29.8 CTS QUALITY YOWAH OPAL - TOP POLISH [EO-55]](https://df2sm3urulav.cloudfront.net/tenants/oa/cache/uploads/images/960000-964999/964458/5fc8bfc1da23c_260x208.jpg)
