Owen Missen @scimissionowen.bsky.social · 30/09/2026Famously versatile and flaky! Graphite's structure is in the high school chemistry curriculum. It conducts electricity and is very soft, leading to its uses in grey 'lead' pencils and as a solid lubricant. Carbon has 5 polymorphs: graphite, diamond, lonsdaleite, chaoite and tartarosite. 0115
Owen Missen @scimissionowen.bsky.social · 30/09/2026Ten years after Mineral Cup began, the mineral that began it all, quartz, is into the semi finals. Quartz is the most common SiO2 polymorph, but there are 8 other known polymorphs of SiO2 (cristobalite, tridymite, coesite, lechatelierite, moganite, seifertite, stishovite and xiexiandeite). 12211
Reposted by Owen MissenMatt Murphy @mjosmurphy.bsky.social · 29/09/2026What a bizarre mineral! I had to vote cuprite. 0288
Owen Missen @scimissionowen.bsky.social · 29/09/2026Cuprite is red as the copper is in copper 1+ oxidation state, not copper 2+ which has the more common blues and greens - competing against halite, best known as an evaporite mineral. Salty fluids are also key to transporting metals in both hydrothermal and surface environments as chloride complexes! 0104
Owen Missen @scimissionowen.bsky.social · 22/09/2026Pyromorphite vs cylindrite, both lead containing minerals but very different! Pyromorphite (Pb5(PO4)3Cl) - apatite structure, found in oxidised zones of lead deposits. Cylindrite (Pb3Sn4FeSb2S14) - sulfide mineral with an unusual cylindrical structural habit, due to incommensurate modulation. 063
Owen Missen @scimissionowen.bsky.social · 21/09/2026Putnisite contains essential chromium - like stichtite yesterday - while julienite's vibrant blue comes not from copper, but from cobalt! Putnisite: SrCa4Cr3+8(CO3)8SO4(OH)16 · 23H2O Julienite: Na2[Co(SCN)4] · 8H2O NB: SCN- is the thiocyanate anion, julienite is the only mineral known with SCN! 173
Owen Missen @scimissionowen.bsky.social · 21/09/2026This is the kind of Mineral Cup match up that is particularly enjoyable for me. Admittedly, neither of these two minerals are common, and nor do they have major uses. But they remind us of the wonder of the natural world and its ability to produce amazing crystals! 1198
Owen Missen @scimissionowen.bsky.social · 18/09/2026A vote for silvery skutterudite is also a vote for bright pink erythrite, vanquished last round in the battle of cobalt-arsenic minerals! Let's join forces rather than revenge vote this time 😅 1102
Owen Missen @scimissionowen.bsky.social · 17/09/2026cassiterite is 100 votes behind, needs a miracle! keep those votes coming! 021
Owen Missen @scimissionowen.bsky.social · 15/09/2026Xocolatlite is a tellurium mineral with a great name, and features in the 10th edition of Mineral Cup, five years after the most unlikely of champions, quetzalcoatlite! Xocolatlite also has the distinction of being described by my phd supervisor Joel Brugger and team! 0125
Reposted by Owen MissenElwyn Rain @elwynrain.bsky.social · 15/09/2026Chrysocolla is beautiful but I had to draw something for Xocolatlite #MinCup26 1197
Owen Missen @scimissionowen.bsky.social · 11/09/2026I confess that before this Mineral Cup I had never heard of julienite! It's our third cobalt mineral of 2026, and is a coordination compound salt containing the thiocyanate anion. You don't see formulae like Na2[Co(SCN)4]·8H2O too often, julienite is the only SCN mineral yet known! 0143
Owen Missen @scimissionowen.bsky.social · 11/09/2026Calcite hardly needs an introduction. Its reactivity with acid and 3 strong cleavage planes (great when teaching first year mineralogy), amazing variety of forms and importance for CO2 storage give us plenty of reasons that calcite might be a favourite. 000
Reposted by Owen MissenHelen MC @crystallised-cricket.com · 10/09/2026Not quite sure how #pyromorphite will fare against the (literal) crystal juggernaut that is #gypsum - but I really liked the (VESTA default) halloween-esque colour scheme to it's elements to day so the small green crystal machine gets my vote in today's #MinCup26 0114
Reposted by Owen Missenspeck @notkaspeck.bsky.social · 10/09/2026Wow wow wow! Giant underground gypsum (selenite) crystals ftw! #MinCup26 1229
Reposted by Owen MissenVicky Veritas @vickyveritas.bsky.social · 10/09/2026Beautiful, twinned, translucent, and hexagonal prisms of lead-bearing, apple-green pyromorphite. Relatively safe if basic safety rules are taken, and highly collectible, but NO licking. #MinCup26 ⚒️ sci-fi 🧪 🖖🏼 scifi Geosciences #WomenInSTEM geology #geosky #GIS 🍎 🪐 🔭 🌋 📚 🌿 46416
Owen Missen @scimissionowen.bsky.social · 10/09/2026Gypsum is a beautifully versatile mineral, found in a range of sedimentary environments, sometimes in flower shaped forms ('desert rose' isn't a flower, but gypsum - often with some quartz grains!). Gypsum is widely used in construction, particularly in plaster and cement-making applications. 052
Owen Missen @scimissionowen.bsky.social · 10/09/2026Pyromorphite sounds like some kind of fire demon, the name actually coming from its behaviour of reforming crystals after being melted into a globule! Old names included 'plumbo viridis' (green lead - pyromorphite being lead phosphate chloride). Vanadinite (V swapped for P) shares this structure! 086
Owen Missen @scimissionowen.bsky.social · 09/09/2026Hafnium's only mineral up against purple putnisite. Second beautiful purple chromium 3+ mineral in two days, with some chemical similarities (group 2 metal - chromium - carbonate - hydroxide - hydrate). Stichtite: Mg6Cr3+2(OH)16[CO3] · 4H2O Putnisite: SrCa4Cr3+8(CO3)8SO4(OH)16 · 23H2O 0102
Owen Missen @scimissionowen.bsky.social · 08/09/2026Stichtite is particularly famous in Tasmania, first found from appropriately named Stichtite Hill (not sure what the previous name of the site was!). It's the most famous mineral first found in Tasmania, although crocoite is Tasmania's state mineral emblem. Both contain soluble chromium! 2127
Owen Missen @scimissionowen.bsky.social · 07/09/2026Monazite doubles as a source of (mainly light) rare-earth elements and as a geochronometer, due to the uranium and thorium often incorporated into its crystal structure . Monazite-(Ce) is the most common form, with La, Nd, Sm and Gd dominant monazites also known in decreasing order of commonality. 1113
Owen Missen @scimissionowen.bsky.social · 06/09/2026Quartz's apparent supremacy as the best mineral was the reason behind Eddie Dempsey creating the first Mineral Cup on Twitter back in 2017! Despite its importance to a wide range of geological and mineralogical sciences, quartz has never yet managed to win Mineral Cup. Could this be the year? 0112
Owen Missen @scimissionowen.bsky.social · 06/09/2026Asagiite is a new member of the ktenasite group, a class of hydrated basic metal sulfates that so far numbers four minerals, so far all in the form MCu4(SO4)2(OH)6.6H2O although analogues with different metals in the Cu site are possible. M=Ni in asagiite 'blue-green' in Japanese! 063
Owen Missen @scimissionowen.bsky.social · 05/09/2026Orpiment was historically used as a pigment, taking advantage of its bright yellow-orange colour. However, orpiment is arsenic trisulfide (As2S3) and thus is very rarely used today. Fellow arsenic sulfide mineral realgar (As4S4) is bright red-orange... and also toxic! 081
Reposted by Owen Missenkadusey @kadusey.bsky.social · 03/09/2026Zinc, gallium, and indium are all fixed points on the International Temperature Scale of 1990 (ITS-90) and are extremely useful for calibrating Platinum Resistance Thermometer (PRT) probes. So sphalerite gets my vote! 193
Reposted by Owen MissenMika McKinnon @mikamckinnon.bsky.social · 04/09/2026#Bournonite has 4 elements. Some lovely rare metals in the mix, and it can solid-solution on over to incorporate a 5th, but it’d very well-defined. Meanwhile, I straight-up gave up listing all the possible elements in #Vesuvianite because it was too freaking long. The rest. It has all the rest. 43913
Owen Missen @scimissionowen.bsky.social · 04/09/2026Bournonite for me! This sulfosalt is formed by lead, copper, antimony and sulfur. Another six minerals contain only these four elements and eleven further sulfosalts have Pb Cu Sb plus other metal(loid)s but bournonite is by far the most common of all of them! 182
Owen Missen @scimissionowen.bsky.social · 03/09/2026Voting for zinc sulfide sphalerite! Sphalerite is also an important host for strategic metal zinc, plus a range of critical metals, especially gallium, germanium and indium (though not usually all three of them in the same crystals). www.mindat.org/photo-253687...mindat.org 042
Reposted by Owen MissenSaavik ‘Careful of the Ankle’ Ford @saavikford.bsky.social · 02/09/2026Argh!!! Neither are blue—yet BOTH can be used to MAKE blue? What do I do??? 2276
Reposted by Owen MissenRebecca Wilcox @rebeccawilcox.bsky.social · 02/09/2026A lot of the erythrite pictures I found look kind of like that cranberry jelly they sell around Thanksgiving, so I guess I’ll vote for the forbidden cranberries. 082
Owen Missen @scimissionowen.bsky.social · 02/09/2026cobalt vs cobalt! hard to pick here, and I love the weathering product vs the primary mineral! 051
Owen Missen @scimissionowen.bsky.social · 01/09/2026carbonate vs carbonate! it's azurite for me, though it still astounds me that the simple form of copper carbonate CuCO3 is not found in nature. copper carbonates always have some OH to stabilise the structures in malachite and azurite! 021
Owen Missen @scimissionowen.bsky.social · 10/11/2025correction from earlier post (about semi final 2 still!), it's native copper vs molybdenite in the final! easier one for me, much as I love copper minerals I'll go with the soft sulfide! 061
Owen Missen @scimissionowen.bsky.social · 09/11/2025quick game's a good game and it's already the Ore Cup final! very hard one to pick for me! both beautiful and important sulfide minerals 🥰🥰 052
Owen Missen @scimissionowen.bsky.social · 08/11/2025correct prediction! we'll see if molybdenite can make it to the final! 040
Reposted by Owen MissenEos @eos.org · 04/11/2025We’re on team #molybdenite in today’s #OreCup match-up. It’s the main ore of molybdenum, a critical resource with many uses, including in building renewable energy technologies. eos.org/features/cri...eos.orgCritical Minerals for a Carbon-Neutral Future - EosThe Earth Mapping Resources Initiative is filling data gaps and fostering more holistic understanding of critical mineral resources in the United States using a novel mineral systems framework. 0217
Reposted by Owen Missenspeck @notkaspeck.bsky.social · 04/11/2025Molybdenite—love those hex shapes, and love this particular speciman’s mix of symmetry and asymmetry. www.mindat.org/photo-298205...mindat.orgMolybdeniteInterpenetrating molybdenite crystals, from the northern end of the quarry. Copyright © 2020 Harold Moritz 0164
Reposted by Owen MissenFrankenGardner @glacierpique.bsky.social · 08/11/2025We didn’t always recognize #Molybdenite or know how to use Mo until the late 19th Century. Rh wasn’t discovered until 1908. After early experiments during WWI, automobile and aviation industries found uses for both elements in high-performance alloys. Then catalysts and medical uses. #OreCup25 ⚒️ 🧪 03010
Reposted by Owen MissenMineral Cup & Ore Cup @mineralcup.bsky.social · 08/11/2025Congratulations to #Copper on a winning by a decisive 27% margin. Whatever happens in the Finals, you won’t be going home with bronze. Condolences, #Ilmenite, but we’re confident you’ll weather this setback with your usual resilience. 0184
Reposted by Owen MissenMineral Cup & Ore Cup @mineralcup.bsky.social · 08/11/2025#OreCup R2M2: It's slippery and silvery #Molybdenite vs peacock rock #Bornite! Are you supporting the only molybdenum (and rhenium) ore, or the hefty copper sulphide? vote: www.mineralcup.org/vote-results... results: www.mineralcup.org/vote-results...mineralcup.orgResults for Semifinals Match 2 — Mineral Cup & Ore CupLive results for Molybdenite vs Bornite 4139
Reposted by Owen MissenDots and Lines @dotsandlines.bsky.social · 06/11/2025Based on the spelling of Carroll, more like: How doth the little mineral Improve its shining face, And hide the cobalt underground, An inconvenient place! 011
Owen Missen @scimissionowen.bsky.social · 06/11/2025#OreCup tis the season! anyone want to write a ... Carroll? O Cobalt Ye Faithful 😅 151
Reposted by Owen MissenNaturae Lapides @naturaelapides.bsky.social · 19/02/2025Carrollite, Japon youtu.be/a_z5HVAkAWk #carrollite #sulfur #quartz #unique #cristaux #cristal #crystals #mineralogie #mineraux #minerai #gemmes #gems #collection #naturae #lapides #minerals #nature #merveille #cristallisation #collector www.youtube.com/@naturaelapi... 072
Reposted by Owen MissenSaavik ‘Careful of the Ankle’ Ford @saavikford.bsky.social · 06/11/2025I have to endorse #Carrollite today—copper PLUS cobalt! 1st I love cobalt blue 2nd cobalt comes from kobold, the German name for an imp or demon, so named bc it made recovery of silver (from ores where they mixed) more difficult to recover. (Yes that’s where D&D got it.) #OreCup 0217
Reposted by Owen MissenJ. Raasch @jraasch.bsky.social · 06/11/2025#carrollite pretty 😍 #OreCup #OreCup25 www.mindat.org/gm/911mindat.orgKamoya South II Mine, Kamoya, Kambove, Kambove Territory, Haut-Katanga, DR Congo 072
Reposted by Owen MissenBill Minarik @silicatefondue.fosstodon.org.ap.brid.gy · 06/11/2025Nice article on the type locality of #carrollite : Carroll County, Maryland and the Patapsco Mine. jamesrada.com/carrollite-the-minera… #OreCup #OreCup25 #MinCup25 #Maryland #Sykesville #Cobalt 0114
Reposted by Owen Missenauthodizer @doktrock.bsky.social · 06/11/2025#Carrollite from Congo at the Tucson show #OreCup #MineralMonday 14310
Reposted by Owen MissenVicky Veritas @vickyveritas.bsky.social · 06/11/2025Octahedral crystals, polysynthetic twinning striations, super conductivity, and iridescent sheen? Yes, please. #carrollite #MinCup25 ⚒️ sci-fi 🧪 🖖🏼 scifi Geosciences #WomenInSTEM geology 🔭🪐 02913
Reposted by Owen MissenMark Shore @markshore.bsky.social · 06/11/2025was planning on voting for bornite until reading that natural specimens of carrollite exhibit superconductivity 😎sciencedirect.comThermodynamic properties and superconductivity of natural carrollite (CuCo2S4)The thermodynamic properties of natural carrollite with a formula Cu0.92Co2.07S4 are studied using low temperature heat capacity and high temperature … 0145