Mount Shadwell Quarry is located in Mortlake at the heart of Victoria’s volcanic region and supplies scoria products to the construction and road works industries. However, the quarry site also contains a rare mineral that can be used in jewellery – olivine.
For more than a decade, Moyne Shire Council, the quarry’s operator, has permitted public access to the site to allow people to fossick for the crystal, attracting geologists, tourists and gemstone club members – amongst others – to the town.
Leah Johnstone, the council’s manager of engineering and design, told Quarry the crystal can be found within hard rock shells – “rock bombs” – that form during the volcanic process, and explained that these bombs can be exposed when scoria is bulldozed from the side of the extinct volcano upon which the quarry is located.
Although the crystals are generally quite small in size, fossickers seek these rock bombs at the quarry site in the hopes of encountering an olivine specimen large enough to be cut to gemstone quality, which by that stage would be called peridot or chrysolite.
Safety a primary concern
The council has taken numerous measures to ensure that the quarry is safe for public access.
Visitors are only allowed in non-operational areas of the quarry, under direct supervision of the quarry supervisor or other authorised personnel.
“All batters in areas where fossickers are permitted are shallower than 3:1,” Johnstone stated.
Prior to entering the site, visitors must agree in writing to obey any directions given to them, stay in allocated areas and only access the site office when accompanied by an escort. In addition, they must sign an indemnity form agreeing to accept all risks associated with the quarry visit.
Once at the site, all fossickers are required to wear high visibility clothing and specified footwear, and to undergo a formal induction process before proceeding into the quarry.
Part of the community
Johnstone stated that the Mortlake community was very supportive of Mount Shadwell Quarry.
“There is a community ‘ownership’ of Mount Shadwell Quarry,” she explained. “Many local farmers and others use its products and the community recognises the economic benefits from the local quarry operating near the town [such as] from visiting fossickers.”
However, due to the impact that fossicking had on staff time and quarry operational efficiency, the council recently decided to introduce a time restriction on public access.
“As Fridays are generally less busy, allowing more time for staff to supervise fossickers with less risk, council now only permits fossicking on that weekday,” Johnstone stated.
Large groups – such as educational facilities – can still enter the quarry on other weekdays, but they would need to book an appointment in advance. Supervised weekend visits are also allowed provided the quarry is not operational.
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