ALVIN, Texas -- A boom heard near Alvin Saturday had some neighbors thinking it was a chemical explosion, a gas leak or that a meth lab had blown up. Christina and Rolando Alvarez were outside of their home just after noon.

"And we hear this really loud boom," said Christina Alvarez. "Like, not just a regular, maybe somebody was shooting a gun, because that’s normal in Alvin."

Two miles from the Alvarez's home, on Brazoria County Road 147, "Man babe! Did you hear that big a** boom? It shook the ground," said Susie Russell as she read a text message from her husband sent to her at 12:21 p.m. Saturday. "And he goes, big a**!"

"Man, it shook the house pretty bad," said Russell as she repositioned a framed photo of her three children. It fell from a wall inside the Russell's home.

"I got on Facebook," explained Alvarez. "Was like, anybody else hear this? What’s going on?"

Dozens of people heard the Saturday afternoon boom. Some told KHOU 11 they heard two back-to-back booms. Others say they heard one. Some neighbors pointed in one direction of C.R. 147, others pointed in the opposite direction.

"I didn't’ think we were going to be that loud," said Janice DeShazer as she laughed in her front yard.

DeShazer lives on 20 acres of property. Saturday afternoon, she hosted family and friends as she mixed together two pounds of tannerite with 15 pounds of blue powder. The mixture was poured into a box positioned in the middle of DeShazer's pasture. Her nephew, Christopher Barnes used a high-powered rifle to shoot at the box. When he did, a plume of blue smoke filled the horizon.

"Honestly, I thought it was a bomb at first," said Alvarez.

The colorful smoke signaled to Barnes and his wife Rae that they're having a boy. Rae Barnes is pregnant with the couple's second child.

A Brazoria County Sheriff's deputy was dispatched to DeShazer's home after people called authorities about the boom. According to the sheriff's office, deputy's have responded to tannerite gender reveals before.

According to the Bureau of Alcohol, Tobacco, Firearms and Explosives, while tannerite does make a boom and there is a plume of smoke, because of it's components in the federal government does not qualify tannerite as an explosive. And because it's not considered an explosive, the ATF does not regulate or monitor the sale of the product.

"And apparently it’s perfectly legal and you can buy it at Academy," said Alvarez of tannerite.

"Just clean, honest fun! And it’s a boy! We’re going to have another boy," exclaimed DeShazer.