Particulates from the object which smashed through the windscreen of 22-year-old Mr Hale's Subaru on State Highway 6 early on October 24 were provided to both Environmental Science and Research and the University of Otago's geology department for analysis.
The material was taken from interior sections of the car which the object came in contact with when it struck and fatally injured Mr Hale, who was driving the car, before exiting through the back window.
The object was never found, despite an extensive search of the area.
Detective Senior Sergeant Malcolm Inglis said yesterday information gained from tests on the material had provided little new information to ''progress the case to any satisfactory conclusion''.
The tests revealed the unknown object was made of, or contained, fragments of stainless steel of a common grade used in vehicle parts and other everyday items, such as tools and cookware.
The object also contained common minerals naturally occurring in soil or dirt in the South Island.
''The stainless steel is very common and really it takes us no further. It could be found in numerous items,'' Det Snr Sgt Inglis said.
The lack of answers provided by the scientific tests was ''really frustrating from a police perspective''.
''We can't get a conclusion or a finality for the family so that they know what's caused this tragedy. They would like to have closure around how Mr Hale came to die, or from what.''
Det Snr Sgt Inglis, who is looking after the case while inquiry head Detective Sergeant Brian Cameron is on leave, contacted Mr Hale's mother in Auckland yesterday morning to inform her of the test results.
''With the death of her son, she is still very upset and would certainly like to progress things further, which we are unable to do at this stage.''
He also spoke with Mr Hale's Alaskan partner Danielle Oylear, who still lives and works in the Lake Hawea area, where the couple had moved shortly before the accident.
Ms Oylear was in the car at the time of the accident and took the steering wheel while lifting Mr Hale's foot off the accelerator pedal.
''Danielle obviously was there and it's still very raw to her and she would like to know what happened exactly, on that day.''
Neither Mr Hale's family members nor Ms Oylear could be reached for comment yesterday.
Det Snr Sgt Inglis said the case remained open and he issued another plea for anyone with information relating to other vehicles or anything else in the area at the time of the accident to come forward.
Investigation findings would now be referred to the coroner.
