Renewable alternative to limestone

EUREKA, Ill. — A company that offers an ocean-sourced limestone replacement is expanding into the Midwest for farmers.

Calcean Minerals and Materials, based in Gadsden, in northeastern Alabama, utilizes oolitic aragonite, a biogenic, ocean-formed version of calcium carbonate that offers a renewable alternative to traditional limestone sources.

Aragonite forms naturally in the Bahamas’ warm, shallow marine waters where calcium-rich water precipitates layer by layer, forming smooth, round grains called ooids.

“Aragonite has some specific attributes that makes it really attractive in the ag space. The first is it has a really high surface area and it has a very high zeta potential. So, you have these charges and interactions at the surface of the aragonite. It has a very high bio-available calcium,” Katie Garrabrant, Calcean director of engineering and research, said at the recent Yield/Profit Challenge plot tour.

“So, we have this calcium that is able to react and to basically integrate into the soil and bring that both pH buffering capability and the calcium content up.”

“Aragonite contains approximately 40% calcium and able to dissolve quickly. Further, aragonite has an innate ability to adsorb nutrients deliverable into fertilizers, efficiently increasing their availability and preventing leaching into sensitive surrounding habitats,” according to the company.

“Aragonite also acts to neutralize volatilization of ammonia. It reduces the hydrolysis of urea by delivering free calcium ions within fertilizers, thereby stabilizing the ammonia.”

“It’s not a miracle by any means, depending on what else the soil has and the health of your plants overall, but it can really help with those things and help drive the nutrients into the plant itself, not just the soil,” Garrabrant added.

Trent Nicholson, owner of Yield/Profit Challenge, is testing aragonite as part of his corn and soybean trials on his farm where the plot tour was held.

“Aragonite has roughly three to four times the energy of limestone. So, a 700-pound application of aragonite will replace a ton of limestone,” said Lynn Hoover, Pro-Soil national field adviser and owner of Ocean Blue Agronomics, who conducted the plot tour with Nicholson.

“It’s a living calcium. Your available calcium determines your volume of yield, as well as your fertilizer availability. This will also drive aerobic activity as well as the natural nitrogen cycle.

“With this whole program of Pro-Soil, the Sea-90 ocean minerals and the aragonite, we can do soil testing next spring and, in some cases, save 50% to 80% of your nitrogen needs, depending on your operation and what’s under your feet.”

Renewable Source

“It’s constantly renewing. In one of our small lease areas, it renews at a rate of 2 million tons a year, and in the bottom in reserves, you have billions of tons. So, the feasibility of running out wouldn’t be in this lifetime,” Garrabrant said.

She was asked why the product’s availability is specific only to the Bahamas.

“There’s only a few places in the world where calcium carbonate, specifically aragonite, is naturally precipitated. It’s kind of a mixture of the perfect temperature and the perfect minerals,” Garrabrant noted.

“There are microorganisms, known as cyanobacteria. They seasonally come and enter the shallow, warm waters of the Bahamas, and they have what’s called a carbon-concentrating mechanism. They sequester and pull CO2 in from the atmosphere. You have this shift in concentration of CO2, which then will drive the mineralization process of calcium carbonate precipitation.

“This is really unique to this area because the Bahamas have primarily calcium as the main mineral in the water. So, what precipitates out is a 96% to 98% pure calcium carbonate.

“We have a very good operation that has an environmental product declaration. It states all of our harvesting procedures, that we do it ethically, we don’t scrape to the bottom, we don’t harm wildlife and we cite that we come in with a negative carbon footprint with our materials.”