I am an archivist for an Australian Catholic religious order. We have a silver chalice that I have been asked to provide provenance for. It has been in Australia since at least 1909, as documented in our records, but we are not sure of its origin. Through comparing the marks on it to marks on this website I believe it is Austrian, late 19th century, as it has a head of Diana inside a flower-shaped cartouche, as well as the HG makers mark. However I can't narrow it down further although it does also have a makers initials. Any help in identifying the maker would be very welcome.
Here is a close up of the maker's marks:
Here is an image of the whole chalice:

