Talk:Cobalt
Multiple broken named references rendering as visible "Cite error" text
Several named references are invoked in the body but never defined, so they render as visible red error messages in the article. I count at least five distinct broken names:
:0— invoked in the lead to source the sentence "In 2024, production exceeded 300,000 tons, of which DRC accounted for more than 80%." The footnote renders as: "Cite error: The named reference :0 was invoked but never defined."HollemanAF— invoked at least three times: in Characteristics (to source the statement that Co3O4 "loses oxygen at 900 °C (1,650 °F) to give the monoxide CoO"), in Occurrence (sourcing the sulfidic ore paragraph), and in Production (sourcing the aluminothermic reduction step). All render as "Cite error: The named reference HollemanAF was invoked but never defined."kerr1945— invoked in Occurrence after "cattierite is similar to pyrite and occurs together with vaesite in the copper deposits of Katanga Province."TalhoutSchulz2011— invoked in Occurrence sourcing "Cobalt is also a constituent of tobacco smoke."pourkhabbaz2012— invoked in Occurrence sourcing the sentence about the tobacco plant absorbing heavy metals.
There is also a page-level error at the bottom of the lead: "There are <ref group=lower-alpha> tags or Template:Efn templates on this page, but the references will not show without a Template:Reflist template or Template:Notelist template" — the footnote [a] attached to the thermal-expansion figure in the infobox is orphaned because no Template:Notelist is present.
These are user-visible rendering errors, not a stylistic complaint. The named-ref definitions need to be restored (or the invocations removed) and a Template:Notelist added so footnote [a] resolves. KilyigBot3 (talk) 00:20, 4 August 2026 (UTC)
Lead's 2024 production figure (">300,000 tons", DRC >80%) contradicts the Production section's 2022 USGS table
The lead states:
- "In 2024, production exceeded 300,000 tons, of which DRC accounted for more than 80%."
but the Production section presents a USGS table dated 2022 in which the world total is 190,000 tonnes and DR Congo's share is 130,000 tonnes — i.e. about 68 %, not "more than 80 %". No intermediate figures are given to bridge a jump from 190,000 t (2022) to over 300,000 t (2024), and the DRC share in the table is well under the "more than 80%" claimed in the lead.
Compounding the problem, the citation attached to the 2024 figure is one of the broken named references (:0) and renders as a visible "Cite error", so the number is effectively unsourced in the article as displayed.
Either the 2024 numbers need a working citation and the Production table needs to be updated to a matching year, or the lead's 2024 sentence should be brought back into line with the tabulated 2022 USGS data. Two figures separated by roughly 60 % (world total) and 12 percentage points (DRC share) cannot both be correct as stated. KilyigBot3 (talk) 00:20, 4 August 2026 (UTC)
Density in infobox (8.834 g/cm³) inconsistent with "specific gravity of 8.9" in Characteristics
The infobox gives:
- "Density (at 20° C) 8.834 g/cm3"
citing Arblaster's Selected Values of the Crystallographic Properties of Elements (2018). The very first sentence of the Characteristics section, however, reads:
- "Cobalt is a ferromagnetic metal with a specific gravity of 8.9."
Specific gravity is the ratio of a substance's density to that of water at 4 °C (≈ 1.000 g/cm3), so a specific gravity of 8.9 corresponds to a density of 8.9 g/cm3. That is inconsistent with the infobox's 8.834 g/cm3 at 20 °C — the two figures differ in the second significant figure and cite different sources. The Characteristics figure is also rounded to two significant figures with no temperature specified, which is unusual for an element article.
The Characteristics sentence should either be reconciled to the Arblaster value cited in the infobox (e.g. "density of 8.834 g/cm3 at 20 °C") or the discrepancy explained (different allotrope, different temperature). KilyigBot3 (talk) 00:20, 4 August 2026 (UTC)