High-Purity Germanium: What 5N Buys

High-purity germanium is sold under one word and four different specifications, and the number most quotations lead with says the least. A certificate reading 99.999% tells you what a commodity lot is worth per kilogram. It tells a detector maker almost nothing about net carrier concentration, an optics shop almost nothing about transmission at 11 µm, and a fibre plant almost nothing about the tetrachloride it actually buys.

That is the whole argument of this page. The four germanium uses that carry the trade, fibre, infrared optics, detectors and solar cells, buy four different documents. The grades below are not steps on one ladder; they are different measurements of different products, and a purchase that compares them by the percentage alone is comparing an offer with a specification.

One boundary up front: this page contains no live germanium price. Spot assessments are sold by price-reporting agencies, and this site has no licensed feed. Every price below is the USGS annual series, which the agency’s own footnote attributes to Argus Media’s non-ferrous assessment, republished. What follows is the published record, dated.

Five high-purity germanium products, four units

The USGS does publish enough to bracket the commodity end. Its 2026 summary puts the 2025 annual average price at $4,100 a kilogram for germanium metal and $2,500 for germanium dioxide, and records that between January and October 2025 the European price for metal at minimum 99.999% purity rose from $3,150 to $5,380 a kilogram, with dioxide going from $2,200 to $2,850.

Read the qualifier in that sentence. Minimum 99.999% is a price-assessment basis, and the qualifier is the agency’s own: it defines the lot being quoted. It does not establish a ladder on which other germanium products sit above or below it.

The 5N label is a price basis, not a grade

The commodity trade in germanium moves in kilograms of metal and dioxide, and the price series exist because there is enough standardisation to quote one. US imports of germanium metal were an estimated 7,000 kilograms in 2025, down 67% from 2024, and dioxide imports were 17,000 kilograms, up 55%. The combined value of those imports was about $66 million.

That is a small trade in absolute terms, and it behaves like one. Net import reliance is above 50%, the tariff schedule prices the forms differently, and the government stockpile carried a potential disposal of 5,000 kilograms for fiscal 2025:

| Form | Tariff | | ------------------------ | ------ | ----------------------------------------------------------------------------------------------------- | | Unwrought metal | 2.6% | | Powder and wrought metal | 4.4% | | Dioxide | 3.7% | When a market is this thin, a purity label plus a delivery basis is most of what can be standardised. |

For a buyer, the consequence is practical: 99.999% is a starting condition. It does not describe inclusions, it does not describe the measurement method, and it does not survive being turned into a crystal.

Detector grade is written in carriers

The clearest evidence that purity percentages stop being useful is the specification for high-purity germanium radiation detectors, which is written in net carrier concentration per cubic centimetre.

Three sources bracket the number, and none of them expresses it as a percentage:

The first row is the manufacturer’s own note (Mirion, HPGe detector notes). A crystal-characterisation paper puts the requirement for high-resolution detectors at roughly 10¹⁰ cm⁻³, and a study of detector-grade material puts it at 10⁹ to 10¹⁰ atoms per cm³ while adding a second requirement the percentage cannot express: a specified dislocation density (HPGe crystal properties).

Getting there is a process story rather than a purity percentage. One study of detector-grade crystals reports the steps (characterisation of HPGe crystals). Commercial germanium metal arrives at a net carrier concentration around 10¹⁴ cm⁻³, measured at liquid-nitrogen temperature; zone refining is the operation that moves it, with about 14 passes taking the concentration down by three orders of magnitude, to roughly 10¹¹ cm⁻³, which the authors call a necessary precursor rather than the finished specification. The refined ingot is then grown into a germanium single crystal by the Czochralski method.

Germanium holds about 4.4 × 10²² atoms per cubic centimetre, so 10¹⁰ per cm³ is roughly 2 × 10⁻¹³ of the atomic density, on my arithmetic from those two figures. As a percentage it rounds to zero at every digit anyone prints. That is why the certificate for detector material lists electrically active impurities and structural defects, and why a supplier quoting a nine or a ten in the purity column is answering a different question.

Optical grade is written in transmission

A germanium lens or window is specified by what it passes and what it loses. Crystran’s data page gives:

Source: Crystran, germanium.

That reflection figure is the one that changes the purchase. Germanium’s index is high enough that an uncoated window throws away more than half the light arriving at it, so an optical blank is nearly always bought together with a coating specification, and the coating is where the cost and the schedule live. A blank certified at 99.999% germanium metal, with no absorption figure and no homogeneity figure, is not an optical component.

Transmission is also not a constant. Crystran’s page notes that germanium becomes opaque at all wavelengths a little above 350 K, about 77 °C, as thermal electrons flood the band gap — which is why an optics buyer needs the operating temperature and the coating specification alongside the band. This is the same lesson as the detector grade in a different currency: the certificate has to name the property the system actually depends on.

Fibre grade is a chemical, not a metal

The largest single use of germanium in the United States is fibre optics, and the route consumes germanium dioxide and germanium tetrachloride rather than metal. Germanium tetrachloride is a chemical feedstock rather than a metal product, and the USGS lists it as an input to fibre glass (USGS, germanium summary).

The USGS records one plant in Quapaw, Oklahoma, making germanium tetrachloride for optical fibre from imported and recycled material, and another in St. George, Utah, making germanium wafers, mostly for solar cells used in satellites. Those two operations sit in the same country and the same supply chain and buy different products with different certificates.

For a sourcing reader this is a fork worth naming explicitly. Asking a tetrachloride supplier for a metal purity certificate, or asking a wafer supplier for a chemical assay of the chloride, gets you either a polite confusion or a document that does not apply.

What the export controls did to the price

China’s export-licensing regime for germanium items came first: Ministry of Commerce and customs Notice No. 23, issued on 3 July 2023 and in force from 1 August, which put the materials under licence and listed five documents an applicant must file, among them a technical description or test report and end-user certification (Notice No. 23). The gallium side of that document is covered in the high-purity gallium guide. Notice No. 23 is no longer the operative text: it was repealed on 1 December 2024, and its six germanium items (metal, zone-refined ingot, zinc germanium phosphide, epitaxial substrates, dioxide and tetrachloride) were reissued as entry 3C002 of the consolidated dual-use list (Announcement No. 51 of 2024). The antimony regime went through the same replacement, into 3C003.

Then the regime tightened for one destination and later relaxed again, which matters for anyone reading a price history. Notice No. 46, dated 3 December 2024, provided that applications covering germanium bound for the United States would, in principle, not be approved (Notice No. 46). Its second paragraph was then suspended by Notice No. 72 on 9 November 2025, until 27 November 2026 (what the suspension does not change; Notice No. 72).

The export series moved around those notices without tracking them exactly. Chinese shipments of germanium metal in the nine months to September were 36,656 kilograms in 2023, 18,787 in 2024 and 7,520 in 2025, and the 2025 volume went mostly to Russia (28%), Belgium (26%), Germany (26%) and Japan (18%). The USGS attributes the American import collapse explicitly to the 2024 ban; for China’s total exports it records the decline without assigning a cause, and the halving between 2023 and 2024 predates Notice No. 46.

The two series did move in the same window: the European assessment for metal rose from $3,150 to $5,380 a kilogram between January and October 2025, with the January reading recorded after Notice No. 46, and the USGS reports the price and export figures side by side without linking them.

So the germanium price series and the material description have come apart. A kilogram figure reflects a licence regime, a destination and a date; the certificate on the box still describes a grade. Reading one without the other is how a buyer ends up paying a 2026 price for a 2023 specification.

Recycling is part of the specification

Secondary germanium is not a side story here, because the streams the USGS names are the products this page has been describing.

The USGS records recycling of new scrap from infrared optics machining, of lenses and windows recovered from decommissioned military equipment, of waste from optical-fibre manufacture, and of germanium wafers used as solar-cell substrates. It also says available information was inadequate to estimate secondary production reliably.

That gap is the purchasing point. A supplier offering reclaimed high-purity germanium scrap and one offering reclaimed wafer stock can both certify the same metal purity and still be supplying different things, so the question is which stream the material came from and what qualification it carries.

What to ask before buying high-purity germanium

Five questions separate a usable offer from a number with a grade attached.

• Which product, exactly: metal, dioxide, tetrachloride, crystal, or polished blank? Each has its own certificate language, and the price basis moves with it.
• What is being measured: a purity percentage, a net carrier concentration, a transmission band, or a chemical assay? Ask for the method, not just the figure.
• What else is in the specification: dislocation density for detector material, absorption and resistivity class for optics, coating for a finished window. The percentage is the shortest line on the page.
• Where it was licensed to go: given the notice history above, the destination and date attached to a lot are part of its provenance, not paperwork.
• Whether it is primary or reclaimed: and if reclaimed, from which stream.

A supplier who answers the first two has a product. One who answers only the percentage has a price. The other material guides sit under industrial materials.

Methodology

This page uses the USGS Mineral Commodity Summaries 2026 germanium chapter for all production, trade, price, tariff, stockpile and recycling figures (2025 estimates, published February 2026); four Chinese ministry notices, each dated and quoted for the change it made; a detector manufacturer’s technical note, a crystal-characterisation study circulated on arXiv and later published in JINST, and a conference-series study for the carrier-concentration requirement, with the refining and growth sequence taken from the characterisation study cited first; and one optical-materials supplier page for the transmission, index and reflection figures.

The 99.999% figure is reported as the basis USGS uses for its price series, not as a grade standard, and the page does not treat one grade as sitting above another. No live or forecast price is stated, no reserve ranking is inferred, and the recycling section reports the absence of a reliable secondary estimate rather than filling it.

Sources

1. USGS, Mineral Commodity Summaries 2026 — Germanium, February 2026. https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-germanium.pdf
2. 商务部、海关总署, 2023 年第 23 号公告（镓、锗相关物项出口管制），2023-08-01 施行，2024-12-01 废止. https://www.mofcom.gov.cn/zcfb/dwmygl/art/2023/art_52b9a321087f402bb3d310d18b07967e.html
3. 商务部、工业和信息化部、海关总署、国家密码局, 2024 年第 51 号公告（发布《两用物项出口管制清单》），2024-12-01 施行；附件 2 为同日废止的十一件公告。 https://www.mofcom.gov.cn/zcfb/dwmygl/art/2024/art_e56833e346534981b250bae772d0cbce.html
4. 商务部, 2024 年第 46 号公告, 2024-12-03. https://www.mofcom.gov.cn/zwgk/zcfb/art/2024/art_3d5e990b43424e60828030f58a547b60.html
5. 商务部, 2025 年第 72 号公告, 2025-11-09. https://www.mofcom.gov.cn/zwgk/zcfb/art/2025/art_5c68985a6b1a46778e2e8dbff1bb1601.html
6. Mirion Technologies, high-resolution gamma-ray spectroscopy with HPGe detectors (manufacturer technical note). https://www.mirion.com/discover/knowledge-hub/articles/education/high-resolution-gamma-ray-spectroscopy-with-hpge-detectors-lab-experiments
7. “Characterization of High-Purity Germanium (Ge) Crystals”, arXiv 2002.07706 (peer-reviewed crystal characterisation). https://arxiv.org/html/2002.07706v2
8. “Study on the Properties of High Purity Germanium Crystals”, Journal of Physics: Conference Series 606 (2015) 012013. https://iopscience.iop.org/article/10.1088/1742-6596/606/1/012013
9. Crystran, germanium optical material data (supplier data page). https://www.crystran.com/optical-materials/germanium-ge/