(CNN) — The Schmitt family has spent every day of the last 13 summers searching for gold off the Treasure Coast of Florida. And it looks like their hard work sifting through trash in the Atlantic Ocean has finally paid off: They’ve just discovered a trove of gold that could be worth more than $300,000.

It started with a single gold coin, spotted over the Labor Day weekend by Dale Zeak, a diver and friend of the Schmitt family. Zeak then spotted more coins and gold chains that he saved for 26-year-old Eric Schmitt, who brought them to the surface Sunday.

"Eric's the one who picked that spot that day," said his sister, Hillary Schmitt. "It was his turn to bring something up."

Eric, who is currently on another dive and could not be reached by phone, shared his experience with HLN affiliate WPTV.

"It was a lot of emotion," he said. "The first was excitement followed by a lot of almost ... crying."

All told, the family's recent discovery included eight gold chains (weighing about three pounds), five gold coins and a gold ring. It's the biggest find the family has ever made, and they've been doing this a long, long time.

Hillary and Eric's father, Rick Schmitt, learned to dive early in life and went on his first treasure hunt when he was a teen. After retiring and selling his pest control business in 1999, Schmitt decided to start a new company, Booty Salvage.

"My dad wanted to share that experience with us kids," said Hillary, 20, who has been diving since she was 5 years old. She adds that there's something special about seeing gold for yourself in the water. "We love doing it. It's a family effort. ... Not only are we doing something that's really fun, we get to do it as a family. It's a pretty awesome experience."

The family leaves the dock every day at 7:30 a.m. during the summer. They'll stay out on their boat, "Aarrr Booty," as long as the weather will allow, usually packing up by 5 p.m. to make it in before sunset.

The latest haul by the Schmitts is likely from a fleet of Spanish ships that was destroyed by a hurricane while returning from a voyage to Cuba in 1715. All 11 ships in that fleet were wrecked, according to Brent Brisben, owner of the 1715 Treasure Fleet - Queens Jewels. His company has the exclusive rights to salvage the remains of that fleet, and he subcontracts the work to several individuals and families, including the Schmitts.

Their find is just one of many made from the fleet since Brisben bought the salvage rights in 2010 at the urging of his dad, who "has been enamored with the allure of treasure most of his life."

Also in 2010, Brisben and his dad discovered a cannon that was stocked with 90 coins (50 gold and 40 silver). Later that year, a mother-daughter team discovered a gold bird, which appraised for more than $800,000.

Brisben said the $300,000 estimate he has given for the Schmitt family's treasure is a conservative one. After the state of Florida takes its 20% share, Brisben said he will split the remainder between his company and the Schmitts.

The family, however, has no desire to cash in their fortune anytime soon. They plan to hand the treasure down to future generations.

"We do not make our living doing this. This is a hobby because, up to this point, we've never found anything like this," said Hillary Schmitt. She added that her family is driven by a shared love for history. She said she hopes their latest find will help them share that love with others.