Fossilised Gastropod ID

[Stephiejayh]

Hi all,

I found some snail fossils and was wondering if I could get them ID'd or even given a ball park age! Location Wollongong Australia. Driving home at the moment but can update with measurements if needed once I'm near a tape measure. Would estimate around 3-4cm or around 1.5inches at their widest part.

[cngodles]

Wollongong looks to be quite a geological mix. Do you happen to know the rock formation this came from? 
 

The shell appears turbinate. The last photo is a steinkern, where the shell dissolves away and leaves a mold of the inside that filled with sediment after burial.

 

Online sources are telling me it could either be Jurassic or Quaternary aged, or simply in an unknown “other geology” zone. I’ll see if I can find a better map.

https://www.bioregionalassessments.gov.au/assessments/11-context-statement-sydney-basin-bioregion/1131-geological-structural-framework

 

I could use a friend in Australia, I’ve contacted a couple museums there with no answer.