An Unusual Way to End Up with a Whole Lot of Gold
theatlantic.com
theatlantic.com
(If the cost of the fusion-made gold was (say) 400X the cost of old-fashioned mined gold - and you also had to wait 15 or so years for its radioactivity to die down - no bright investors who want to help scale that up.)
Also, can't be used immediately: there is a 16 years period before radioactivity comes down to a safe level.
So I'd say it can be introduced smoothly, and make the endeavor of of a reactor more lucrative while not destroying gold market.