Frank Holmes, CEO and chief investment officer of US Global Investors, stopped by the Investing News Network booth at the recent Vancouver Resource Investment Conference to talk about gold prices, gold mining stocks, and what to expect for 2016.Overall, he stressed that the strong US dollar has been a boon for gold mining companies in countries such as Canada or Australia. "If you look at some of the Australian gold producers we own, they're up 300 to 700 percent in a year," he said.In terms of what to expect from the gold price, Holmes first stressed that gold is quite volatile, and that it would be "a non-event" for gold to gain or lose 20 percent over a twelve-month period, pointing to real interest rates in the US as the catalyst to watch for."Do we start seeing inflation rise, and rates don't rise? That would be a trigger for gold to take off," he explained.Other highlights from our conversation included:The favourite large-cap stock from US Global Investors (Hint: It's a royalty company)The top pick stock from Holmes from the mid-tier gold producer spaceHolmes's thoughts on how investors can assess the future of larger diversified miners such as Teck Resources (TSX:TCK.B) and Freeport McMoRan (NYSE:FCX)Watch the video above for US Global Investors's favourite big-cap stock, as well as Holmes's top pick from the mid-tier producer space.