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Diamond Brand® Ferrous (Iron) Sulfate

Moist Ferrous Sulfate Heptahydrate | Dried Ferrous Sulfate Heptahydrate | Dried Solu-Grade® Heptahydrate | Dried Ferrous Sulfate Monohydrate | Dried Ferrous Sulfate Granular Monohydrate

Moist Ferrous Sulfate Heptahydrate (Fe~18%) – 50 Lb. bags or 2,000 Lb. bulk bags
Moist Ferrous Sulfate Heptahydrate crystals contain approximately 8% exterior or free water and is the least costly of all of the various forms of ferrous sulfate available from Verdesian. Having the consistency of damp salt, moist ferrous sulfate does not flow freely like the dried forms of ferrous sulfate and has to be mechanically transported when being mixed with water or other substances.

At our manufacturing facilities in Cape Girardeau, MO and North Lima, OH, we always maintain large inventories (+10,000 tons) of moist ferrous sulfate for immediate shipment in bulk or super sacks. This allows us to respond to large volume ferrous sulfate requirements in a short period of time.

Dried Ferrous Sulfate Heptahydrate (Fe-20%) – 50 Lb. bags or 2,000 Lb. bulk bags
The most commonly used form of ferrous sulfate is Dried Heptahydrate, due to its consistent iron, sulfur, water and oxygen contents, its free-flowing characteristics, and its ability to go into solution rapidly. It can be shipped in 50 lb. bags or bulk bags.

Although our Diamond Brand Dried Ferrous Sulfate Heptahydrate is free-flowing when processed, this material has a tendency to compact and/or cake (becomes hard) under various shipping and storage conditions. These hardness problems occur due to the instability of the sixth and seventh molecules of interior water (H2O), which have a tendency of releasing from each heptahydrate crystal when stored in temperatures in excess of 75° F, or in extreme humid conditions. Upon request, and at no additional cost, Verdesian can add an anti-caking agent to extend storage times of dried heptahydrate and help to prevent caking or compaction. 

Dried Solu-Grade® Heptahydrate (Fe-20%) – 50 Lb. bags or 2,000 Lb. bulk bags
Diamond Brand Dried Ferrous Sulfate Heptahydrate (FeSO4•7H2O) Solu-Grade is derived from a co-product of the steel pickling industry. We segregate raw materials from a select group of steel pickling operations to assure the purest, lowest insoluble content, and brightest blue/green color for our Solu-Grade product. This makes Solu-Grade the obvious choice for applications such as liquid fertilizers where clarity of solution and low insolubles are required. The agricultural, lawn and garden, and turf management industries use our Diamond Brand Ferrous Sulfate to correct iron chlorosis or deficiencies in plants and soils, to eliminate moss, to reduce alkalinity, and as a trace element or micronutrient in fertilizers.

Dried Ferrous Sulfate Monohydrate (Fe-30%) – 50 Lb. bags or 2,000 Lb. bulk bags
Ferrous Sulfate Monohydrate contains the greatest amount of Iron per ton (Fe-30%) and the least amount of interior water (one molecule or ~12% by weight). At Verdesian, ferrous sulfate Monohydrate is made in three sizes:

  1. Standard or powdered size (US Sieve Mesh Size -20 +100)
  2. Fine Granular (US Sieve Mesh Size of -16 +24)
  3. Coarse Granular (US Sieve Mesh Size of -6 +16)

All three sizes will not compact or cake in transit or in storage as long as it is not exposed to free water or temperatures in excess of 325° F. In addition, the higher iron content of Monohydrate results in lower transportation, bagging and palletizing costs per pound of iron by as much as 33% when compared to the same costs per pound of iron contained in moist and dried ferrous sulfate Heptahydrate. The primary disadvantage of dried ferrous sulfate Monohydrate is its slower rate of solubility due to its higher iron content.

Dried Ferrous Sulfate Coarse and Fine Granular Monohydrate (Fe-30%) – 50 Lb. bags or 2,000 Lb. bulk bags
Verdesian proudly offers its premium grade Diamond Brand Granular Ferrous Sulfate Monohydrate which is primarily used as a fertilizer ingredient for turf, ornamental, and agricultural applications. As the ONLY domestic producer of granular ferrous sulfate Monohydrate in North America, we wax coat and double screen our product for dust control and enhanced handling characteristics. This allows us to offer a harder de-dusted granule that is ideal for bulk blenders who strive for premium quality.

At Verdesian, our Dried Ferrous Sulfate Granular Monohydrate is available in two sizes:

  1. Fine Granular (US Sieve Mesh Size of -16 +30, SGN 100)
  2. Coarse Granular (US Sieve Mesh Size of -6 +16, SGN 230).

OMRI Listed
Verdesian’s Diamond Brand Ferrous Sulfate products are now OMRI listed and allowed with restrictions. Our iron sulfate products may be used as a plant or soil amendment if soil deficiency is documented by testing. Please see ORMI’s website for additional information regarding our Diamond Brand OMRI listing.

The Diamond Brand® Ferrous (Iron) Sulfate was previously owned by the QC Corporation, which was acquired in 2014 and changed its name to Verdesian Life Sciences 2016.


For information or orders, contact Bob Bundschuh.

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