# Thallium ## 🧊 Thallium · 3D (three.js) <iframe src="https://wikitube-elements.netlify.app/?el=Tl&embed=1" width="100%" height="620" frameborder="0" style="border:0;border-radius:12px;overflow:hidden" allowfullscreen loading="lazy" title="The Elements 3D microsim - Thallium"></iframe> *Thallium in the live three.js Elements explorer — drag to orbit the atom, click any tile to compare, slide the temperature.* · [▶ open full](https://wikitube-elements.netlify.app/?el=Tl) <!-- ELEMENTS_MICROSIM:END --> !Thallium plate.svg *Plate 81 of 118 - animated Bohr shells, stylized per Madelung filling; engraving style per house Arcanity kit.* ## Microsim To Do *Claimable rows, house pattern. Real Wikipedia articles only.* - Spectroscopy - William Crookes and the green line that revealed thallium - Optical fiber - thallium compounds in infrared detectors and lenses - Cardiac imaging - thallium-201 in nuclear medicine - Rodenticide - the toxicology history of thallium compounds ## Links (Wikipedia order) <!-- injected from _registry/childlinks/Thallium.json (2026-07-30T02:09:12Z) --> `A_Greek–English_Lexicon` · `Abundance_of_elements_in_Earth's_crust` · [[Actinium]] · `Alkali_metal` · `Alkaline_earth_metal` · [[Aluminium]] · [[Americium]] · `Anode` · [[Antimony]] · [[Argon]] · [[Arsenic]] · [[Astatine]] · [[Atomic_mass]] · `Atomic_number` · `Atomic_radius` · `August_Wilhelm_von_Hofmann` · [[Barium]] · [[Berkelium]] · [[Beryllium]] · [[Bismuth]] · `Block_(periodic_table)` · [[Bohrium]] · [[Boiling_point]] · `Bolometer` · [[Boron]] · `Boron_group` · `Brinell_hardness_test` · `Bromide` · [[Bromine]] · `Brookhaven_National_Laboratory` · `Bulk_modulus` · `Buoyancy` · `CAS_Registry_Number` · `CRC_Handbook_of_Chemistry_and_Physics` · `CRC_Press` · [[Cadmium]] · [[Caesium]] · `Caesium_chloride` · [[Calcium]] · [[Californium]] · [[Carbon]] · `Carbon_group` · `Cement` · `Centers_for_Disease_Control_and_Prevention` · [[Cerium]] · `Chalcogen` · `Charles_Frédéric_Kuhlmann` · [[Chemical_element]] · `Chloride` · [[Chlorine]] · [[Chromium]] · `Claude-Auguste_Lamy` · `Clay` · `Close-packing_of_equal_spheres` · [[Cobalt]] · `Commission_on_Isotopic_Abundances_and_Atomic_Weights` · [[Copernicium]] · [[Copper]] · `Coronary_artery_disease` · `Covalent_radius` · `Crookesite` · `Crystal` · [[Crystal_structure]] · `Cuprate` · [[Curium]] · `Cyclopentadienyl` · `Cyclotron` · [[Darmstadtium]] · [[Decay_chain]] · [[Decay_product]] · [[Density]] · `Dimethylmercury` · `Dipyridamole` · `Disproportionation` · `Doping_(semiconductor)` · `Double_salt` · [[Dubnium]] · `Ductility` · [[Dysprosium]] · [[Einsteinium]] · `Electrical_resistivity_and_conductivity` · `Electrolysis` · 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`Hemoperfusion` · `High-temperature_superconductivity` · [[Holmium]] · `Hutchinsonite` · `Hydrochloric_acid` · [[Hydrogen]] · `Hydroxide` · [[Indium]] · `Infrared_detector` · `Insecticide` · `International_Atomic_Energy_Agency` · [[Iodine]] · `Ion_transporter` · [[Ionization_energy]] · [[Iridium]] · [[Iron]] · `Ischemia` · `Isotope` · `Isotopes_of_thallium` · `Journal_of_the_Optical_Society_of_America` · `Kelvin` · [[Krypton]] · [[Lanthanum]] · `Lattice_constant` · [[Lawrencium]] · [[Lead]] · `Lead_chamber_process` · `Linear_motor` · `List_of_chemical_element_name_etymologies` · `List_of_data_references_for_chemical_elements` · [[Lithium]] · [[Livermorium]] · `Lorándite` · [[Lutetium]] · [[Magnesium]] · `Magnesium_battery` · [[Magnetic_resonance_imaging]] · `Magnetic_susceptibility` · `Magnetism` · [[Manganese]] · `Manganese_nodule` · `Mary_Elvira_Weeks` · [[Meitnerium]] · `Melting_point` · [[Mendelevium]] · [[Mercury_(element)]] · `Metal-halide_lamp` · `Mineral` · 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`Technetium-99m` · `Technetium-99m_generator` · [[Tellurium]] · [[Tennessine]] · [[Terbium]] · `Thallane` · `Thallide` · `Thallium(I)_bromide` · `Thallium(I)_carbonate` · `Thallium(I)_chloride` · `Thallium(I)_fluoride` · `Thallium(I)_hexafluorophosphate` · `Thallium(I)_hydroxide` · `Thallium(I)_iodide` · `Thallium(I)_oxide` · `Thallium(I)_sulfate` · `Thallium(I)_sulfide` · `Thallium(I)_telluride` · `Thallium(III)_acetate` · `Thallium(III)_oxide` · `Thallium_barium_calcium_copper_oxide` · `Thallium_halides` · `Thallium_poisoning` · `Thallium_trifluoride` · `Thallium_triiodide` · `Thallous_acetate` · `Thallus` · `Therapeutic_index` · [[Thorium]] · [[Thulium]] · `Timeline_of_chemical_element_discoveries` · [[Tin]] · [[Titanium]] · `Tonne` · `Toxicology_Letters` · `Triiodide` · `Tuberculosis` · [[Tungsten]] · `United_States_Environmental_Protection_Agency` · `United_States_Geological_Survey` · [[Uranium]] · `Van_der_Waals_radius` · [[Vanadium]] · `Vapor_pressure` · `Vasodilation` · [[Wayback_Machine]] · `William_Crookes` · [[Xenon]] · `Young's_modulus` · [[Ytterbium]] · [[Yttrium]] · [[Zinc]] · [[Zirconium]] > **Official MAIN - Chemical element, Z = 81.** Part of the Elements Canon (one canonical page per element). Infobox grounded in [Wikipedia: List of chemical elements](https://en.wikipedia.org/wiki/List_of_chemical_elements), fetched 2026-07-08. Full article: [Wikipedia: Thallium](https://en.wikipedia.org/wiki/Thallium). <!-- ELEMENTS_MICROSIM:BEGIN (auto-managed block - edits inside will be overwritten) --> ## Key facts (infobox) | | | |---|---| | Symbol - Z | Tl - 81 | | Group - Period - Block | 13 - 6 - p-block | | Atomic weight (Da) | 204.38 | | Density (g/cm3) | 11.85 | | Melting - Boiling (K) | 577 - 1746 | | Electronegativity (Pauling) | 1.62 | | Crustal abundance (mg/kg) | 0.85 | | Origin | primordial | | Phase (STP) | solid | | Name origin | Greek thallos, 'green shoot' | *Bracketed weights are the mass number of the most stable isotope; values in parentheses are predictions (per the source table).* ## Story Thallium was discovered in 1861 by the British physicist William Crookes while analyzing zinc ore residues using spectroscopy—the element's characteristic green spectral line (its name comes from Greek *thallos*, "green shoot") made it unmistakable. It is a rare post-transition metal with chemical behavior similar to lead and potassium, which can make it dangerously bioavailable. Thallium is highly toxic in its compounds and historically was used as a rodenticide (particularly in the mid-20th century) until health risks became apparent. Today, its primary industrial use is in fiber optics and infrared detectors—the element's optical properties make it valuable for specialized lenses and crystals. Thallium is also used in some radiopharmaceuticals for cardiac imaging. [model-prior - verify] In the Elements Canon, thallium sits in group 13 (the boron group) at the edge of the transition metals, a region where stability begins to give way. Like the nearby noble metals and lead, it carries a historical reputation from its poisoning use—a mirror to the toxicity profiles tracked in the canon's occupational-health and industrial-history semiotic frameworks. ## Corpus connections Thallium connects to the canon through its role in toxicology, spectroscopy, and the post-transition-metal framing that bridges chemistry and occupational health. - R.E.A.C.T.I.O.N. - the Chemistry hub - Centers of Excellence Portal - [[Technetium|Technetium - the element made before found]] - the canon's patron - and Technitium, the School - [Spectroscopy](https://en.wikipedia.org/wiki/Spectroscopy) - thallium's green line was pivotal in its discovery and use in emission spectral analysis ## Vocational-Technical Semiotics The element speaks the canon's shared signs: the periodic table cell (Tl, group 13, period 6), isotope notation, and hazard pictograms ghs where handling demands it. ## Sources Infobox: [en.wikipedia.org/wiki/List_of_chemical_elements](https://en.wikipedia.org/wiki/List_of_chemical_elements) (fetched 2026-07-08); etymology per the same table's notes. Story sources to be added at enrichment. ## Navigation - Canon: Elements Canon index - neighbors by Z: [[Mercury_(element)|Mercury (80)]] - [[Lead|Lead (82)]] - R.E.A.C.T.I.O.N. - Centers of Excellence ## Wikipedia : Wikitube **Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Thallium) : [Wikitube](https://en.wikitube.io/wiki/Thallium) ## Previous hub tags Tree parents: [[Helium]] · [[Hydrogen]] · [[Oxygen]]. Legacy hubs: none. --- *Sources: 1 legacy note. Minted wave 1, 2026-07-30 (v1.6 order).*