Gidgee timber would provide a reasonable test. A supplier,
http://www.thetimberjoint.com/contact/

It is all moot anyhow, given that if wood or rock (incl volcanic glass and Kimberly points) are not implicated, a possible explanation is that an Aborigine obtained a metalic object that had been traded in the North of Oz and happened to clout another Aborigine with it.

There were dozens of aboriginal clans and there were forever giving one another a nasty touch-up with nulla-nullas and war boomerangs made from fire hardened timbers like Gidgee root.

From the given information there is nothing, zilch, nada to support any attempt at historical revisionism to peddle a narrative of 'frontier wars'

Yes eBay has mulga weapons at $hundreds and I've tried suppliers - have a post in woodwork forum, some bloke may have an offcut 2 foot long.
In Melbourne, a Ngurungaeta today visits schools as headman of the region.
Patna City Anthem पटना नगर-गीत nagara gita (Skr nagasya gitam) of Patna.
Indonesian .nagara : country. gita hymn. song.

William Barak - Wikipedia,

1824 – 15 August 1903), was the last traditional ngurungaeta (elder) of the ...
" Murrundindi (aka Gary Hunter) is the ngurungaeta of the Wurundjeri people, a descendant of William Barak.
Each of these clans was governed by an individual or group of senior men who had the title ngurungaeta. These individuals were men of distinguished achievement who had effective authority within their clans and 'were considered its rightful representative in external affairs'. ..

Parampara - Wikipedia,
en.wikipedia.org/wiki/Parampara

Parampara denotes a succession of teachers and disciples in traditional Vedic culture and Indian religions such as Hinduism, Sikhism, Jainism and Buddhism. It is also ...

http://ngarrindjeri.jay019.com/

ngarrindjeri.jay019.com/culture/ngurunderi.php

The two fought a great battle. Ngurunderi eventually killed Parampari and burnt his body near Kingston.

arrrg... can't edit posts.
the weird text is Sanskrit-Hindi writing from India.
Maybe a sword drifted across from north Oz to Bourke but difficult to imagine it being traded away repeatedly across tribes.
The Darling river legend is about a giant fish-man Pundu who was chased by Ngurunderi on a raft made of reeds. This made waters flow down the fish's pathway to the south sea. He cut up the fish to make all types of other fish.
The raft is Lalangenggal.

Murray River - Wikipedia, the free encyclopedia
The twin summits of Mount Misery are supposed to be the remnants of his rafts, they are known as Lalangengall or the two watercraft.

- Ngurunderi Dreaming – Hearing Ngurunderi coming, his wives just had time to build a raft of reeds and grass-trees and to escape across Lake Albert.
Balinese. lalang :reeds. anggal : fast.

In Indonesia , the Hindu text Matsya Purana is about a giant fish-man
who was tied to the boat of Manu in a flood. The fish was Vishnu the preserver of life and the boat carried 7 wise man and seeds to replant the world.
Indonesian "pandu" means guide, as in the national song about "pandu" for the goddess, partner of Vishnu who had a fish-symbol in artwork.
_Pandom was the ship-compass which used to be a magnetic fish floating on oil. The Pandya kings of south India for over 1000 years had a fish symbol on flags, coins and temples. They traded and settled in Indonesia.

nicknamenick, "Maybe a sword drifted across from north Oz to Bourke but difficult to imagine it being traded away repeatedly across tribes"

It hasn't been established that it was a sword. I suggest that speculation is white man academic dreaming. -Just as a aside, I would venture that I am not the only 4X4 traveller into country and remote areas who has heard indigenous elder criticism of the politically correct white revisionist history.

As I suggested earlier, there is a richer history to be found, but not while white academics and professionals milk guvvy grants and get involved in politics and activism.

Notwithstanding that, I would question the assumption that a novelty item such as an edged weapon from Asia could not have been transported to far flung places via trade/ceremonial routes. However, an edged weapon like a sword would not have been valued by Aborigines, being cumbersome and ill-suited to lifestyle. In any event, the edge is quickly lost and difficult to maintain. It would be a 'ship's anchor' to a nomadic.

For what it is worth,

http://www.qhatlas.com.au/content/aboriginal-dreaming-paths-and-trading-ways

Given the huge variety of traditional edged tools and weapons of Indonesia and other close Asian countries, the utility and greater ease of maintenance of those items which along with tradition encouraged personal carry and the established frequency of fishermen from that region to the north of Australia and Queensland, it is astounding that a researcher might surmise it was a sword of 'European' or 'British' origin.

Foxy,

Anyone who thinks that they can find 'intent of murder' in a cut on a skull of that age or any other, without knowing the facts surrounding the incident is in cloud nine land or is being misquoted.

Mulga might well do a decent cut and a lot would depend upon just how tough the skull was when new.