Commodities
Chrome ore and concentrate: the specifications that matter
Chromite is sold on Cr2O3 content, chrome-to-iron ratio, impurities, size and moisture. Learn how to read a chrome specification and compare offers.
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What chrome ore is used for
Chrome ore, also called chromite, is the only commercial source of chromium. Most of it goes to the metallurgical industry, where it is smelted into ferrochrome, an alloy added to steel to make stainless steel. Smaller volumes go to chemical plants to make chromium chemicals, and to foundries and refractories. The end use decides which specification the buyer wants.
The main specification lines
Cr2O3 content
The percentage of chromium oxide is the main value driver. Metallurgical-grade ore is commonly in the range of roughly 40 to 48 percent, while chemical and foundry uses can ask for different grades. Concentrates produced by upgrading lower-grade ore aim to raise the content.
Chrome to iron ratio
The Cr:Fe ratio shows how much of the ore's metal content is chromium compared with iron. A higher ratio gives a ferrochrome alloy with more chromium per ton, so buyers pay more for it. Ferrochrome producers set a minimum ratio.
Impurities
Silica, alumina, magnesia, phosphorus, sulphur and carbon-related elements are limited. Phosphorus and sulphur matter because they are harmful in steel. Maximum limits are common and a penalty scale applies above them.
Size
Lumpy ore, chips and fines or concentrate are different products. Submerged-arc furnaces prefer coarse material for gas flow, while fines usually need agglomeration, such as pelletising or briquetting. Contracts give a size range and the maximum share of undersize or oversize.
Moisture
Moisture adds weight that is not ore, and wet fine material can be a handling and shipping problem. Contracts state a maximum and say whether the price applies to the dry weight.
Grades by use
- Metallurgical grade: for ferrochrome smelting, with a focus on Cr2O3, ratio, size and low phosphorus.
- Chemical grade: for chromium chemicals, with limits on elements such as silica and iron that affect the chemical process.
- Foundry and refractory grades: where sand or brick properties matter, so physical properties are key.
Pricing
Prices are quoted per metric ton, often on a basis of a stated Cr2O3 content, for example per ton at a base grade, with adjustments above and below. Many contracts price per unit of Cr2O3, so a change of one point changes the total. Published market assessments exist, and many deals reference them with a premium or discount. The terms to settle are the base content, the adjustment per point, the penalty and rejection limits, the Incoterm and the load port.
Sampling, analysis and umpire
Because small differences affect the price, sampling is the heart of the contract. The contract should say who samples at loading, which standard method applies, how many sealed parts are made and which laboratory is final. If the buyer's and seller's results differ by more than the allowed tolerance, an umpire laboratory result normally decides. A moisture determination is needed along with the analysis, and the weight basis should be clear.
Shipping and paperwork
Chrome ore usually ships in bulk or in containers, and it is a dense, heavy cargo, which affects stowage and the vessel's loading plan. Typical documents are the bill of lading, commercial invoice, certificate of origin, certificates of weight and analysis, and a moisture certificate. Check export licences and any duties at origin, since rules change by country.
Questions to ask a seller
The Chrome channel in the Deal Room is the place for questions about specifications and typical contract terms.
- Which mine or plant produces it, and which recent analysis can you share?
- What is the current stock position and shipment schedule?
- Is the offered product lump, chips, fines or concentrate, and what is the size range?
- Which inspector and laboratory do you propose, and is the result binding?
Frequently asked questions
- What does Cr2O3 mean?
- It is chromium oxide, the compound used to express how much chromium an ore contains. The percentage in the sample is the main quality figure.
- Why does the chrome-to-iron ratio matter?
- Ferrochrome producers want more chromium per unit of iron. A higher ratio gives a richer alloy, so it is worth more.
- Can fines be used in a furnace?
- Usually after agglomeration such as pelletising or briquetting, because fine material can block gas flow in the furnace. The buyer's process decides.
- Who decides if analyses differ?
- The contract should name an umpire laboratory and a tolerance. Without it, disagreements are hard to settle.
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