What is IODEX?
Platts Iron Ore Index, or IODEX (IODBZ00), is a benchmark assessment of the spot price of physical iron ore. The assessment is based on a standard specification of iron ore fines with 62% iron, 2.25% alumina, 4% silica and 0.09% phosphorus, among other gangue elements.
Since the breakdown of annually negotiated prices in 2010, IODEX has been the primary physical market pricing reference for seaborne iron ore fines delivered into China, the biggest importer of the steelmaking ingredient.
The use of the IODEX has also been extended to price iron ore in the forms of lump, pellet and concentrate, via the application of premiums and discounts to account for quality differences from the base specification.
The assessment is published on a CFR Qingdao basis, but is used by steelmakers, traders and mining companies globally to price long-term and spot contracts.
Ores delivered on quality, location and timing dimensions differing from those underlying the IODEX are normalized using impurity penalty/premia differentials, which are updated to reflect prevailing market values for different impurities.
IODEX and accompanying iron ore price assessments have brought increased transparency to an industry which continues to evolve in terms of the pricing methods it employs, most recently manifest in the forms of floating price deals for physical cargoes, hedged using positions in the financial derivatives market.
The Platts Iron Ore (IODEX) price assessments are available in these services. 
For over 10 years, S&P Global Platts has provided robust and independent price assessments for iron ore. This video outlines the key processes that our editorial team undertake when assessing the iron ore market, including the important role of Platts Market-On-Close (MOC) process. For more information email: IODEX@spglobal.com.