How does triple superphosphate differ from ordinary superphosphate?

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Ordinary superphosphate and triple superphosphate differ primarily in their manufacturing process and their concentration of useful phosphorus, expressed as phosphoric oxide.

Ordinary Superphosphate: This is produced by treating phosphate rock with sulfuric acid. This process results in a product that contains "dead weight" in the form of calcium sulfate, limiting its useful phosphoric oxide content to approximately 20 percent.1
Triple Superphosphate: This variety is produced by replacing sulfuric acid with phosphoric acid during the treatment of phosphate rock. Because this method eliminates the formation of calcium sulfate, all the calcium from the original rock is converted into monocalcium phosphate. This increases the useful phosphoric oxide content to about 45 percent, effectively more than doubling the concentration of the nutrient and significantly reducing the amount of material that must be transported and distributed.1