Sodium Borate
Sodium Borate is a unrated form of Boron, used in 371 on-market products and providing 11.3% elemental boron by weight.
371
on-market products
unrated
quality tier
11.3%
elemental fraction
Basis: Na2B4O7 x 10H2O, borax decahydrate (MW 381.37; anhydrous sodium tetraborate would be 0.215) -- hydration on labels not stated, decahydrate assumed
Why this tier: No head-to-head human bioavailability or efficacy comparison of this form was located in PubMed searches.