Diamonds At Diamond Hill?

i live about 30 mins from diamond hill near kurrajong nsw.
i have seen limited info suggesting that diamonds and other gemstones can be located in this area due to volcanic activity millions of years ago leaving basalt.
i may even head out there today and post back info myself
any info on this area or info on locating gems in basalt would be appreciated.

It's private property, I've often thought of checking it out as well as my parents live nearby. I don't think it's a verified diamond location though, just a rumour that an old bloke once found one there. The only access there is down I think Brown's Road to a firetrail which actually goes to Little Wheeny Creek about a km or 2 down from Diamond Hill.

Waste of time in my opinion, Oberon is a much better bet for hunting gemstones.

Here's some info on it.

203419 - Diamond Hill Diatreme
(Kurrajong, Blue Gum Creek)
Coords: -33.527640,150.667224
Mga_coordsys: MGA_56S
Mga_north: 6287780
Mga_east: 283365
Loc_method: 25K
Accuracy: 500
Grid_loc: arbitrary point on Blue Gum Ck near diatreme
Major_comm: diamond - gem
Size_code: OCC
Comm_type: GEM
Met_prefix: SYDNEY
Geo_province: Sydney Basin
Metal_dist: not assigned
Op_state: not operating
Op_status: never worked
Op_method: no workings
Lga: Hawkesbury
Compiler: SR Lishmund 23/09/1998
Last_update: 1998-09-23
Occur_size: Occurrence only
Notes: Diamond reported to have been found in basalt in the diatreme. MacNevin reports find may have been a xenocryst which could scratch glass. Location uncertain.
Commodities
diamond - gem MAJOR
Current Resource Estimates
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Production
---
Minerals
---
Mineralisation Style
---
Host Rock
(volcanic breccia) Volcanic Breccia
Relation to Host
---
Alteration
---
Ore Texture
---
Placer
---
Classification
---
Deposit Shape
---
Stuctures
---
Current Tenements
---
Project References
---
References
MacNevin A.A. (1977) Diamonds in New South Wales 2018-10-12 DocType:Mineral Resources

Thanks for your reply I actually went to Oberon twice since this post, with some luck bit of gold and two little Saphs for my first time so Yea I guess Oberon is the go. Would you be able to recommend any specific spots I tried to access porters retreat and don't think I ever really found the fossicking area

Yes, one local resident claimed to have found one diamond there, but no one else has seen it I think. A number of people on this site have made similar claims. How would he have known better?

Jebus said:

I tried to access porters retreat and don't think I ever really found the fossicking area

Click to expand...

Hi Jebus,
To get to Porters Retreat -
1. Head south on the Abercrombie Rd from Black Springs until you see a sign announcing the town of Porters Retreat (there is no actual town).
2. A couple of klms on you come to the bridge over Retreat River.
3. Cross the bridge. The fossicking area is on the right side of the bridge (note the Shooters Hill Rd turn-off is on your left).
4. About 50mtrs south of the bridge on your right, you will see a small dirt track leading back towards the river. It is negotiable by a 2WD vehicle if you take care.
5. Travel about 50mtrs and park on top of the hill. Don't attempt driving down to the river unless in a well set up 4WD.
6. Fossicking area is the river from the bridge west to a fence and sign saying "private property". Then from the river, all the way up the hill south to a boundary fence.
Porters Retreat has been well and truly dug over through the years, but nice blues and parti-coloured sapphires are sometimes still found there as well as zircons and maybe a little fine gold.

Watch out for "brown nuggets" if digging up the hill - for decades there were toilets in the area. :lol: :lol: :lol:
Cheers.

Thanks I'll be sure to let you know if I make it next time

Drop toilets are still there. Noticed years back that some one had been digging towards the dunnies. :lol:
Not a good idea.

A fair bit of the original diggings were filled in donkeys years ago as a safety measure.
Can be very hit or miss digging in places.

jimnyjerry said:

Drop toilets are still there. Noticed years back that some one had been digging towards the dunnies. :lol:
Not a good idea.

Click to expand...

Someone probably told them there were nuggets to be found near the toilets. :lol:

Today's drop toilets are further west and a bit higher up the hill from where I remember them about 40 years ago.
And I also remember there had been some very large, deep diggings near the old toilets too.

Heatho, in these geological reports when it says Size_code: OCC or minerals in occurrence what do they really mean by occ? Be it gold or gemstones. Does it mean there may be 1 pin head speck or how much?
Cheers.

Anyone have an answer to the previous post please?

It appears to me it qualifies an occurrence that may or not be of any value; stating only an occurrence, reasonable or otherwise.

Definition of mineral occurrence
i. The presence of useful minerals or rocks in an area under examination.

Ref: Shanz

ii. A concentration of a mineral (usually, but not necessarily, considered in terms of some commodity, such as copper, barite, or gold) that is considered to be valuable or that is of scientific or technical interest. In rare instances (such as titanium in a rutile-bearing black sand), the concentration of the commodity might be less than its average crustal abundance.

Thankyou. I.e. they have nfi. but know someone once found mineral there.

It has to do with whether it was economical to extract.

Deposit Size: Size of the deposit using the MRLIS 1967 size classification based on the value at 1967 prices of production and/or reserves of commodities. The categories are: occurrence = less than $10,000 (or unknown); small = $10,000-$1,000,000; medium = $1,000,000-$10,000,000; large = $10,000,000-$100,000,000; very large = >$100,000,000.

Taken from http://dwh.minerals.nsw.gov.au/CI/metadata.php?dataset=DEP

We used to cap drill sites that had an economic value of 4ozs of gold per tonne - because the mineral occurrence we were looking for was nickel that had an extraction value that returned a higher profit on the minerals exchange.