The project includes the flagship 1.3 million ounce Okvau deposit.
Emerald can earn the stake by sole-funding a definitive feasibility study, an environmental and social impact assessment, and a $US3 million, two-year exploration program.
Renaissance has previously estimated that the cost of the DFS and EISA alone would be $4-5 million.
The July 2015 prefeasibility study envisaged capital costs of $120 million for a 1.5 million tonne per annum, eight-year operation to produce around 91,500 ounces of gold per annum at life-of-mine all-in sustaining costs of $731 an ounce, using a $1100/oz gold price.
The PFS returned a net present value of $90 million, a post-tax internal rate of return of 19% per annum, and a payback period of 3.2 years.
The farm-in deal comes after a long hunt for cashed-up Emerald, led by former Regis Resources chief operating officer Hart, and featuring other former Equigold management on the board.
Hart said Okvau and the surrounding area had demonstrated excellent potential.
"We will focus on the development economics of the Okvau gold deposit by optimisation of capital and operating costs through process design and mining efficiencies as we have been able to deliver on gold projects in the past," he said.
Emerald has also participated in Renaissance's $A3.4 million placement, subscribing for 57.4 million shares at 3c per share for $1.74 million.
The investment will give Emerald a 10% stake in Renaissance, as well as giving it the right to appoint a director to the board.
Emerald has cash and liquid investments of $17.4 million.
Renaissance managing director Justin Tremain said the Emerald team was one of the best credentialed gold development teams in Australia.
"The fact that this team has been attracted to the Okvau project is a testament to its potential," he said.
Given its roots in oil and gas, Emerald shares will remain suspended while the company meets listing requirements surrounding the change of activities, which is likely to take until April.
Renaissance shares dropped 9% to 3c, in line with the capital raising price.