Delivery to Storage


U.S. Borax refinement processes help improve your shipping, handling, and storage experience
by reducing the potential for dust and caking. Follow these recommendations to ensure
optimal product performance.


Convenient sizes for manual handling  


Optimal quantities for large-scale industrial applications 




U.S. Borax packaging is designed to provide maximum protection and satisfactory results when reasonable care is taken during storage and handling.

Our bagged products are typically supplied in 50 lb (25 kg) bags. We pack these products in multiwall kraft-paper bags incorporating a polyethylene barrier layer. For added protection, pallet shipments are stretch-wrapped.

Borates are also available in Intermediate Bulk Carriers (IBCs). These containers are constructed from white woven 100% polypropylene, with or without polyethylene liners depending on customer preference. We primarily ship 2,500 lb sacs in North American markets and 1,100 kg super bags elsewhere.

Other sizes are available for specialty products.


Shipping of bagged products is arranged through our sales team, who ensure timely and cost-efficient deliveries by optimizing point of origin, freight modals, and delivery details to best meet each customer’s needs.


Handle bagged borate products with care. Avoid puncturing bags. A hole in a bag not only results in spillage but might expose the product to moist air, which can cause caking. Punctured bags also increase the potential for product contamination.


The storage (shelf) life of U.S. Borax borates depends on many factors. Most borates are relatively stable, so when stored and handled according to recommended practices, our products have demonstrated the ability to remain free-flowing and suitable for a year or more after packing.

For optimal results:
  • Keep containers in a dry warehouse
  • Store product off the floor on wooden pallets, limiting pallet layers
  • Do not stack pallets on top of each other for extended periods
  • Keep temperatures less than 85°F | 29°C
  • Maintain a relative humidity of less than 45%
  • Always use the First In/First Out (FIFO) principle: Use the oldest material first.
If prolonged storage is necessary, reduce caking tendencies by rolling individual bags on a clean, dry surface. Lumps that are caused by compaction generally crumble easily; do not confuse lumps with the hard caking that results from changes in water content. Caked material is chemically unchanged and suitable for most industrial applications. In the case of borax decahydrate EP, NF, and SP grades, we recommend NOT storing the product in a controlled atmosphere below 60% of relative humidity. If necessary, changes in water content can be determined in a laboratory.

Expected shelf life of borates
Borates are chemically stable indefinitely when stored in the original, intact packaging in a dry and covered warehouse. Therefore, the concept of an expiration date is not typically applicable.





Trucks and containers can typically ship a bulk load of 18 to 28 tons; railcars, 100 to 110 tons. Before converting to bulk shipment, we suggest working with your supplier to determine the most appropriate transport system.

Trucks are generally equipped with their own pneumatic discharge systems, operating at pressures of about 29.4 psi (2 atmospheres). These trucks can deliver into silos up to a height of 100 ft (30 m). Avoid long horizontal runs of piping.

Railcars generally have a bottom gate for discharge between the tracks. However, some cars are equipped for pneumatic discharge—either with their own pneumatic systems or using your equipment. The average hopper car is approximately 4,450 ft3 (126 m3) and holds 100 tons (90,700 kg). Cars are available upon request, with dual systems for unloading via either gravity or pneumatic methods. All cars are equipped with center dump gates.

Containers (with or without liners) are emptied by gravity or by suction using the customer’s equipment.


Ideally, unloading and transfer equipment should be sheltered from direct rainfall. Caking (as opposed to mild consolidation) usually occurs only when the material becomes wet as a result of a massive ingress of water.

Gravity unloading
Use an air-operated impact wrench to open and close the slide gate, which can bind with the buildup of product in the slide tracks. Product can then be discharged at a controlled rate from the track hopper, through an adjustable slide gate, to a mechanical conveying system, and then to a storage silo.

Pneumatic unloading
Neobor and Optibor are nonabrasive, so this procedure can be used to easily convey these products directly from the car to the silo. A flexible hose with quick coupler is usually attached to a side port on the car; the other end is attached to permanent piping that runs parallel to the silo. This unloading method prevents the product from being exposed to the elements and eliminates the potential for contamination from outside sources.

Borax decahydrate contains a higher percentage of water than either Neobor® or Optibor®, making it more prone to caking. Therefore, although pneumatic unloading is possible, mechanical unloading is strongly recommended. If pneumatic unloading is used, gravity discharge the product through a double-finger crusher and into a holding bin before pneumatically conveying it to the silo.

Transferring product

Mechanical conveying systems
These systems include belt conveyors, screw conveyors, and centrifugal bucket elevators. Electric or air vibrators mounted near the discharge opening of the track hopper can facilitate discharge, if necessary. Mechanical systems should incorporate sealed transfer chutes or dust extraction.

Pneumatic conveying systems
These systems have the advantage of being dust-free. Neobor, Optibor, and borax decahydrate can be air conveyed by pneumatic pipe systems or air slides. Because of its abrasive nature, Dehybor® requires the use of ceramic or hard-faced liners at specific points where abrasive wear is expected such as elbows, transition pieces, and impingement surfaces in cyclones, diverters, and receivers.

Transfer tips
When conveying borax decahydrate via air slide, use the same precautions as for pneumatic unloading (gravity discharge through a double-finger crusher and into a holding bin before conveyance). Use only dry, cooled air and be sure to maintain air conveying temperatures below 95°F (35°C). Air conveyance is not recommended for locations that are frequently humid with high ambient air temperatures.


Mechanical conveying systems
When storing bulk borates in silos, use either concrete or mild steel. Do NOT use steel silos to store Optibor due to potential corrosion problems. (Learn more in our technical bulletin.)

Although most bulk borates can be stored in silos, some can cake if storage is prolonged (due to the product’s hygroscopic nature).

Although Granubor® products are designed to resist physical degradation, dropping the product into storage bins or silos can increase the potential for damage to the granules.


U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving 650 customers with more than 1,800 delivery locations globally. We supply around 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles northeast of Los Angeles.  Learn more about Rio Tinto.

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