Polysilicon: Correlation
Prices it moves with, and why
Polysilicon is ultra-pure silicon made by converting metallurgical silicon to trichlorosilane and depositing it at high temperature. Costs are dominated by silicon metal and electricity, and price follows solar demand and large swings in Chinese capacity.
No public price Polysilicon has no public monthly price series: Traded on Chinese spot quotes behind paywalls; no public series here.What its price moves with
Metallurgical-grade silicon, smelted from quartz with carbon, is reacted with hydrogen chloride to make trichlorosilane. Silicon metal is the largest raw material cost, and its price in turn depends on Chinese power costs and quartz supply.
No public price for silicon, so the link is explained in words only.Hydrogen chloride turns silicon into trichlorosilane, and most of it is recycled in closed loops at modern plants. It is therefore a minor cost, but the link explains why polysilicon plants often sit beside chlor-alkali complexes.
Not enough overlapping price history to measure.The deposition process uses very large amounts of electricity, and much Chinese capacity sits in coal-powered Xinjiang and Inner Mongolia. Cheap coal power is a core reason China makes most of the world's polysilicon.
Not enough overlapping price history to measure.Almost all polysilicon goes into solar wafers, so solar installations set demand. Overbuilt Chinese capacity pushed polysilicon prices below cost from 2023, which in turn made solar modules much cheaper for buyers in India and elsewhere.
No public price for solar photovoltaics, so the link is explained in words only.Silver paste and polysilicon are both key solar cell materials, so a solar boom lifts demand for both at once. Silver's price is set mainly by investors and the wider precious metals market, so the link is only partial.
Not enough overlapping price history to measure.How to read these numbers
Correlation of monthly changes (the number in the coloured pill) compares how much each price moved, month by month, since 2006 or the first month both series exist. It runs from −1 to +1: near +1 the two usually rise and fall in the same months, near 0 there is no link, and a negative number means they tend to move in opposite directions. Above 0.7 is strong, 0.4 to 0.7 moderate, 0.2 to 0.4 weak.
12-month changes compare year-on-year moves, which shows whether two prices share the same cycles even when the month-to-month noise differs.
Price function is a straight-line fit of the two prices on logarithmic scales: price ≈ k × (partner price)β. β is how much this price moves, in per cent, for a 1% move in the partner over the whole period, and R² is the share of the variation the fit explains. Two prices that both drift up with inflation can fit well without any real link, so read it together with the monthly correlation.
Lead or lag checks whether the monthly correlation is clearly higher when one price is shifted by 1 to 6 months.
Correlation is not cause. The reasons on each card explain the economic link; the numbers show how strongly it has shown up in prices. Proxy series are US producer price indexes or related prices and can blur the real link.
Data: World Bank Commodity Price Data (Pink Sheet), October 2026; US Bureau of Labor Statistics producer price indexes, IMF primary commodity prices and US EIA prices via FRED, Federal Reserve Bank of St. Louis, retrieved November 2026. Calculations by this site.