Yerilla Chrysoprase Mine, Yerilla Station, Menzies Shire, Western Australia, Australiai

Regional Level Types
Yerilla Chrysoprase Mine	Mine
Yerilla Station	- not defined -
Menzies Shire	Shire
Western Australia	State
Australia	Country

13 kilometres south of the Yerilla Station homestead. Two pits- the old Yerilla Mine and New Pit. Historic information is in short supply, the present owners even have found little in this regard. They have confirmed mining for at least 12 years prior to 2007, when they took over. Chrysoprase from the mine has been seen as specimens occasionally internationally, and more commonly in local collections from fossicked material. Mining of chrysoprase in the past has seen the material exported to Asia to be carved into 'jade' objects.

Chrysoprase from Yerilla shows a refractive index of 1.54 (spot), and specific gravity of 2.60.

Chrysoprase has also been mined to a limited degree from an open-cut operation 5 kilometres east south-east of Mount Catherine on the station (Fetherston, 2007). Minor mining is said to have occurred in 1992. No further details are given although it would place it close to the Boyce Creek nickel prospect.

The chrysoprase at Yerilla occurs in swarms of green veins throughout an ironstone caprock, overlying a hill of ultramafic rock. It is found as ellipitcal pods to a few centimetres, long stringers up to a metre in length, and angular masses of various sizes. Chunks less than 25mm -100mm thickness contains veins of white to grey chalcedony, nodules of white magnesite, and bright green chrysoprase veins. Analysis of the chrysoprase shows antigorite and quartz is present. The mine also produces attractive lemon-yellow to light yellow magnesite specimens, which go by a variety of local names like Citron, Lemon Prase and Lime Prase.

The writer is yet to confirm on the ground details, although satellite images indicate the site is not easily accessed with no clear access track. There has however been plenty of chrysoprase mined here in the past, and has been a popular fossicking site with those who can find it. The new and old pits mentioned in the references may virtually be co-joined according to images. Fetherston confirms there are two leases. Several minor workings one kilometre to the east is thought to be part of the Ovens gold mine, but needs confirmation. Fetherston stating the mine is north of the Cranky Jack Road-Yarri Road intersection appears to be at odds with the further comment it is 13 kilometres south of the Yerilla homestead.

(Fetherston, 2007) also calls the location Boyce Creek East, although if the Mindat co-ordinates are correct the creek itself is several kilometres to the east. It also briefly mentions a Boyce Creek location which may be the same as that described above east south-east of Mount Catherine.

Other Regions, Features and Areas containing this locality

References