The Value of Refined Borates

Research shows that not all boron sources are equal in their ability to provide plants with soluble boron throughout the season.

In the tests below, all samples were of similar particle size.

U.S. Borax products are fully refined to remove impurities and maximize potential plant uptake. This process results in a pure, natural product that provides optimized nutrition throughout the growing season.

The U.S. Borax refining process involves several important steps:

1. We mine high-quality sodium-borate ore that is naturally low in calcium and other contaminants
2. We dissolve the ore in water
3. We settle the dissolved borate liquor to remove impurities
4. We cool the liquor and then further wash and filter the resulting crystal slurry
5. We dry the refined slurry to produce dry borate crystals
6. We check our products for purity, solubility, consistency, and optimal granulation
7. We constantly conduct and review field tests and other research to improve our products and services

Production Process of Refined Borates at U.S. Borax 

Crude Ulexite Ore from Other Borate Providers

Most other borates go through only minimal (if any) processing. These products are merely washed, dried and calcinated, and granulated. As a result, they are typically less soluble, contain more contaminants, are inconsistently sized, and provide less reliable boron availability rates than refined boron.


 

IMPURITIES

Other impurities, such as arsenic, also compromise the quality of some borate products. Our studies of fertilizer samples show arsenic content of as much as 157 ppm in samples of Turkish 10% boron ore, while Chilean 10% boron ore can contain as much as 1,500 ppm. By comparison, U.S. Borax refined Granubor^® contains less than 5 ppm.

 

Supplier	% of B	Water Solubility B	CaO	Arsenic content (ppm)
Turkish	15%	5.4%	19%	141
Turkish	15%	5.4%	0%	<20
Turkish	14%	4.7%	0%	151
Turkish	10%	7.4%	21%	157
Chilean	10% (granular)	5.2%	22%	1500
Peruvian	10% (granular)	5.9%	12%	962
Granubor	15%	15%	0%	<5