Natural Red Iron Oxide - Applications & Uses
Haemetite, most commonly known as rust, is a chemical compound of iron and oxygen. In the industrial realm it is known as red iron oxide and is one of the most important minerals. This compound of iron and oxygen is only one of sixteen known oxyhydroxide variants. As a granulated powder it makes an excellent cost effective colourant. Red iron oxide is one of the oldest pigments to be used by every major civilization.
Naturally occurring as deposits in crystalline form, variations of haemetite can be found around the world. Even far away on Mars, red iron oxide is available naturally. On Earth, it coexists with several other minerals including chalk, clay, and quartz. Readily available in several forms, only two forms are specifically used as a colourant and can be used in the production of industrial, commercial, and household products including:
Colourant, Pigment, and Dyes
The company African Pegmatite has a large global footprint with over 170 million coloured bricks produced every year. Qualities as a colourant include permanency and dependability with extensive opacity and tinting strength. Additionally, haemetite is indifferent to alkalis, does not react with solvents, but are partially soluble in acids.
The red colouring provides UV protection, and provides non leeching containment which is important to products like beer, wine, pharmaceuticals, and oils, and for plate glass for residential, commercial, automotive, and architectural use.
Clay and Ceramics
Used to color clay in shades of red and terracotta. After firing, ceramics using red iron oxide are vibrant and distinct from other variations of colouring.
FDA (US Food and Drug Administration)
Approved medical and cosmetic grade colourant, named ‘Red 101’ is used in:
- Dental composites,
- Cosmetics and beauty & personal care goods. Since the early 1900’s red iron oxide has been used in this context. Highly sought for cosmetics for being non-toxic, moisture resistant, and not known to cause allergic reactions (even in those with sensitive skin). Adding titanium oxides, many shades of lighter red to pink are created. Used in many products including lip gloss, lipstick, blush, eye shadow, soaps, lotions, creams, powders, soaps, facial and body masks, and scrubbing salts.
- Tattoo inks – it has been recently verified in studies that products inserted under the dermis as permanent makeup, tattoos, and even some temporary tattoos can lead to some iron and nano particles gradually being absorbed by the blood vessels, causing fading and potential slightly elevated mineral levels in blood.
Cement, Concrete, Pavers, and Blocks
Using only one part haemetite and three parts grey cement will create a deep red cement colour, and many variations are used in modern walkways, parks, and private and public recreational areas. For concrete applications, a ratio of 5 to ten percent is used. Also used with a variety of colored pavers and blocks for creative paving of walkways, driveways, patios, firepits, and masonry work.
Best suited to indoors for homes and industrial use, red oxide flooring is very cost efficient, durable, and appealing for its’ luxurious shine that ages well.
For durability, roofing tiles are a great choice, weather durable, though can fade over long stretches of time. This type of roof can last from 15 to 30 years, and do not need to be sealed or resealed unlike the common misnomers in the public. Depending on the base material, such as concrete or clay, some red iron oxide roofs can last 50 to 100 years. It is important to understand that tiles mistreated may break, and should be replaced appropriately to maintain the life of the entire roof.
Plastics and Rubber
- PVC, Polyolefins, PS, ABS, engineering polymers,
- Silicone items
- Rubber items in a vast array, such as gaskets, stoppers, and playground balls.
Polishing and Buffing
- Powder – usually mixed with an emollient and used for polishing fine silver.
- Waxes and greases – used for polishing metals, antiques and reproductions.
- Jeweler’s rouge – light abrasive used with a soft cloth for final polishing on fine metals in jewelry and lenses.
Iron and Steel Industry
Used as feedstock for the production of steel, iron, and several composites and alloys.
Used in nanopartical form, for the processing and data storage.
Emulsions and Coverings
- Paints – acrylic, tempura, fresco, watercolors, oil based, and rust-hindering versions.
- Primer for metal and wood – creates a solid layer for hinder rust and bleed-through.
- Glazes – for ceramics to provide all shades and tints of pink to maroon.
- Stains – used for wood and plaster applications.
- Fingernail polish
Calamine lotion – this well known shade of pink uses haemetite at a mere .5 percent, as the active ingredient to relieve mild itching.
High Heat-Resistance Coatings
Used for boilers, flues, and ovens for temperatures up to 90 Celsius. Can be used on the interior or exterior surfaces.
Used in a paste style materials for smoothing out imperfections and deep scratches on cars, wood, or metal-based items. Once dried and sanded, can be primed and painted to perfection.
The nanopartical form can be used in unique applications for medical purposes using its’ paramagnetic properties such as reverberation imaging, marking carcinogenic tissues, attractively controlled delivery of pharmaceuticals, and thermotherapy.
Surprisingly, as mentioned above, haemetite is non-toxic. There is only one related health caution. The concern is the potential lung irritation that comes from inhaling excess amounts of fine dust. Wearing proper gear or encasing the powder remedies this minute issue. Carefully mixing liquids into powder is important as well whenever handling sizable amounts of red iron oxide powders.
As you can see with the list above, there is a wide use for red iron oxide. With constant change and developments in the production of goods, electronics, and biomedical fields, we could be in for a big surprise of the uses of this naturally abundant mineral in the future.