The 15-year-old, of Dunedin, has more than 500, but his favourite at the moment is a 65-million-year-old ammonite (Kossmaticeras bensonia).
The extinct mollusc, collected from the Fairfield sand quarry, was placed first in the junior fossil section at the New Zealand Rock and Mineral Competition held in Dunedin this week.
Fossils, minerals and rocks caught his attention when he was aged 4, and he joined the Otago Rock and Mineral Club when he was 7.
"We've gone on a couple of field trips. You go and look for the concretions and hope there will be a fossil inside," he said.
It was uncovering something so old which attracted him to fossil hunting.
"I've always been interested in it. I want to study geology."
Club committee member Stuart Laughton said the national competition, hosted by the Otago club for the first time in more than 25 years, attracted more than 300 entries from 60 people.
The entries, divided into sections such as jewellery, fossil and mineral, were judged on Thursday night in 87 different classes and went on public display yesterday.
The fossil section was one of the best as the specimens were "really strong around Dunedin", he said.
The show, and a sale section, is open at Forbury Park Function Centre from 9am to 5pm today and tomorrow.