@scimissionowen

Lecturer in Environmental Mineralogy at CODES @UTAS_ , focusing on Critical Elements! I also enjoy hiking and tennis. Views my own.

 Hobart, Tasmania
Joined May 2017
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New mineral alert! My first new mineral, wildcatite, is officially published - a calcium iron tellurate hydroxide, CaFeTeO5(OH). It is named for the small gold prospect in which it was found, Wildcat prospect in Utah, USA, which I visited in 2018. doi.org/10.3749/canmin.20000… (1/7)
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Congratulations to our Mineral Cup 2026 Champion Quartz! For #MinCup26, we collectively chose a nostalgic beauty of resilience as persistence as our champion. Please celebrate #Quartz, a friend to humans since time immemorial! mineralcup.org/about/2026-qu…
A single quartz point, deep violet in its core and entirely clear around the outside, with ghostly traces of the crystal's former shape inside, as well as a few tiny bubbles.

ALT A single quartz point, deep violet in its core and entirely clear around the outside, with ghostly traces of the crystal's former shape inside, as well as a few tiny bubbles.

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Cuprite is still in with chance! Copper does form a few Cu 1+ minerals but mostly these are sulfides or sulfosalts e.g. chalcocite (Cu2S), as an oxide mineral cuprite is unusual!
Mineral Cup #MinCup@MineralCupOct 1
#MinCup26 FINALS!!! We have a pair of geometric beauties as deep red #Cuprite is against versatile #Quartz. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split image of fine red needles of cuprite on one side and chunky clear quartz crystals on the other.

ALT Split image of fine red needles of cuprite on one side and chunky clear quartz crystals on the other.

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Graphite's flat sheets means it conducts electricity and is very soft, leading to its common uses in grey 'lead' pencils and as a solid lubricant. Carbon has 5 polymorphs: graphite and diamond are the best known, lonsdaleite, chaoite and tartarosite make up the rest.
Mineral Cup #MinCup@MineralCupSep 30
#MinCup26 Semifinal 2 It’s a match sure to break hearts between industrial powerhouses piezoelectric #quartz and lubricating #graphite! (With the correct links this time!) VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo between a pair of glassy-clear terminated quartz crystals and flaky blades of dark grey graphite at odd angles to each other, with green crystals around them.

ALT Split photo between a pair of glassy-clear terminated quartz crystals and flaky blades of dark grey graphite at odd angles to each other, with green crystals around them.

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Owen Missen retweeted
rikora@rykryzSep 29
Kawazulite (Kawazu mine, Shizuoka Pref., Japan)
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Ten years after Mineral Cup began, the mineral that began it all, quartz, is into the semi finals. It comes up against graphite, famously versatile and flaky. Quartz is the most common SiO2 polymorph, but there are no less than 8 other known polymorphs of SiO2!
Mineral Cup #MinCup@MineralCupSep 30
#MinCup26 Semifinal 2 It’s a match sure to break hearts between industrial powerhouses piezoelectric #quartz and lubricating #graphite! (With the correct links this time!) VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo between a pair of glassy-clear terminated quartz crystals and flaky blades of dark grey graphite at odd angles to each other, with green crystals around them.

ALT Split photo between a pair of glassy-clear terminated quartz crystals and flaky blades of dark grey graphite at odd angles to each other, with green crystals around them.

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Cristobalite, tridymite are somewhat common; coesite, lechatelierite, moganite, seifertite, stishovite and xiexiandeite are much less household names - except perhaps amongst high pressure mineralogists!
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Cuprite 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.
Mineral Cup #MinCup@MineralCupSep 29
#MinCup26 SEMI-FINALS!!! It's showdown of the soft and cubical as coppery #Cuprite and salty #Halite compete for a spot in the finals! Both are worthy, but only one can have your vote. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of a translucent deep red cube of cuprite within swooping matte blue-green crystal blades and a scattering of translucent white halite cubes in a nest of golden yellow spiky crystals.

ALT Split photo of a translucent deep red cube of cuprite within swooping matte blue-green crystal blades and a scattering of translucent white halite cubes in a nest of golden yellow spiky crystals.

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Pyromorphite vs cylindrite, both lead containing minerals! 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.
Mineral Cup #MinCup@MineralCupSep 22
#MinCup26 Round 2 Match 6: It's a pair of soft, heavy lead minerals as vivid hexagonal phosphate #Pyromorphite is against spiralling rolled sheets of #Cylindrite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of clusters of small green puffball-spiked lime green pyromorphite clusters on a rusty-red rough porous rock and Metallic grey fibrous sheets and swirls of cylindric that resemble pencil shavings more than a mineral

ALT Split photo of clusters of small green puffball-spiked lime green pyromorphite clusters on a rusty-red rough porous rock and Metallic grey fibrous sheets and swirls of cylindric that resemble pencil shavings more than a mineral

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A 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 😅
Mineral Cup #MinCup@MineralCupSep 18
#MinCup26 Round 2 Match 2 It’s a match of opposites as heavy metal toxic #Skutterudite is up against the colourful sparkly aluminum silicate jewelry gem #Vesuvianite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of the pointy end of a rough, geometric metallic crystal and a translucent yellow striated tower with a blunt top

ALT Split photo of the pointy end of a rough, geometric metallic crystal and a translucent yellow striated tower with a blunt top

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cassiterite is 100 votes behind, needs a miracle! keep those votes coming!
Mineral Cup #MinCup@MineralCupSep 16
#MinCup26 Round 1 Match 16 It's a pair of industrially-vital minerals for the final match of the first round as tin ore #Cassiterite is up against elemental carbon #Graphite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of cassiterite crystals, silvery to shiny black, in shapes similar to faceted gemstones and a flat, hexagonal graphite crystal jutting up, dark grey with a greasy shine.

ALT Split photo of cassiterite crystals, silvery to shiny black, in shapes similar to faceted gemstones and a flat, hexagonal graphite crystal jutting up, dark grey with a greasy shine.

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Xocolatlite 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 @JoelBrugger and team!
Mineral Cup #MinCup@MineralCupSep 15
#MinCup26 Round 1 Match 15 It's blue vs red for vibrant cyan-blue #Chrysocolla vs rich chocolatey red-brown #Xocolatlite. Are you with the hydrous copper silicate or the tellurate? VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of rounded towers of aqua-blue crystals resembling a puffer spike ball and radial splats of reddish-brown crystals resembling lichen growth.

ALT Split photo of rounded towers of aqua-blue crystals resembling a puffer spike ball and radial splats of reddish-brown crystals resembling lichen growth.

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I 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
Mineral Cup #MinCup@MineralCupSep 11
#MinCup26 Round 1 Match 11 It's a pair of minerals that pull off near-magical tricks with their properties as ubiquitous #Calcite is up against rarity #Julienite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…

Vote in Round 1 Match 11 — Mineral Cup & Ore Cup

Vote in Calcite vs Julienite Credit: Harold Moritz and David Hospital

mineralcup.org
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Calcite hardly needs an introduction. Its reactivity with acid (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.
Mineral Cup #MinCup@MineralCupSep 11
#MinCup26 Round 1 Match 11 It's a pair of minerals that pull off near-magical tricks with their properties as ubiquitous #Calcite is up against rarity #Julienite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…

Vote in Round 1 Match 11 — Mineral Cup & Ore Cup

Vote in Calcite vs Julienite Credit: Harold Moritz and David Hospital

mineralcup.org
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Gypsum 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!). Gypsum is widely used in construction, particularly in plaster and cement-making applications.
Mineral Cup #MinCup@MineralCupSep 10
#MinCup26 Round 1 Match 10: It’s a pair of soft minerals that form near the surface as heavyweight #pyromorphite is up against evaporate #gypsum. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of a scattering of highlighter-yellow log-shaped Pyromorphite crystals and a dense cluster of translucent white flat, rounded gypsum crystals that resemble a flower bud

ALT Split photo of a scattering of highlighter-yellow log-shaped Pyromorphite crystals and a dense cluster of translucent white flat, rounded gypsum crystals that resemble a flower bud

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Pyromorphite 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 - for obvious reasons, pyromorphite being lead phosphate chloride).
Mineral Cup #MinCup@MineralCupSep 10
#MinCup26 Round 1 Match 10: It’s a pair of soft minerals that form near the surface as heavyweight #pyromorphite is up against evaporate #gypsum. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of a scattering of highlighter-yellow log-shaped Pyromorphite crystals and a dense cluster of translucent white flat, rounded gypsum crystals that resemble a flower bud

ALT Split photo of a scattering of highlighter-yellow log-shaped Pyromorphite crystals and a dense cluster of translucent white flat, rounded gypsum crystals that resemble a flower bud

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Hafnium'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). Plus sulfate in putnisite. Putnisite: SrCa4Cr3+8(CO3)8SO4(OH)16 · 23H2O
Mineral Cup #MinCup@MineralCupSep 9
#MinCup26 Round 1 Match 9: It’s a pair of tiny minerals with unusual chemistry as hafnium-containing #Hafnon battles with strontium/chromium-containing #Putnisite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of jagged dark brown to orange opaque crystal grains of hafnon embedded in an unidentified white matrix and tiny grape-jello purple cubical crystals with a rough surface. The crystals are poking out of a massive rough rock with areas of fuzzy green and broad purple, all with a grainy coating of white as though it were rubbed with flour

ALT Split photo of jagged dark brown to orange opaque crystal grains of hafnon embedded in an unidentified white matrix and tiny grape-jello purple cubical crystals with a rough surface. The crystals are poking out of a massive rough rock with areas of fuzzy green and broad purple, all with a grainy coating of white as though it were rubbed with flour

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Stichtite is particularly famous in Tasmania, first found from appropriately named Stichtite Hill (not sure what the previous name was!). It's the most famous mineral first found in Tasmania, although crocoite is Tasmania's state mineral emblem. Both contain soluble chromium!
Mineral Cup #MinCup@MineralCupSep 8
#MinCup26 Round 1 Match 8: It’s a pair of soft and lovely minerals as Stichtite and Talc compete for your votes. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo with a rough chunk of vividly purple stichtite with occasional dark speckles and a pearly white talc with cool green undertones and a flaky surface.

ALT Split photo with a rough chunk of vividly purple stichtite with occasional dark speckles and a pearly white talc with cool green undertones and a flaky surface.

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Monazite 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 of monazite, with La, Nd, Sm and Gd dominant monazites also known.
Mineral Cup #MinCup@MineralCupSep 7
#MinCup26 Round 1 Match 7 It's a color-changing match of informative minerals! Time-tracker #Monazite-(Ce)'s yellow in sunlight darkens to orange in incandescent light, while index mineral #Andalusite is pleochroic. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo with yellow andalusite, backlit to show its color and its growth patterns, which have four-fold symmetry with branching dark streaks in each direction and a glassy amber-yellow crystal point in a craggy setting of smaller, lighter yellow crystals.

ALT Split photo with yellow andalusite, backlit to show its color and its growth patterns, which have four-fold symmetry with branching dark streaks in each direction and a glassy amber-yellow crystal point in a craggy setting of smaller, lighter yellow crystals.

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Asagiite 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 🇯🇵!
Mineral Cup #MinCup@MineralCupSep 6
#MinCup26 Round 1 Match 6 It's a classic vs a newbie as the most common named mineral in the crust #Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago #Asagiite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of clear quartz points radiating from a central point, with amethyst purple at some of the tips and cool mint green asagiite in mostly log-shaped crystals, with a few blobby bits.

ALT Split photo of clear quartz points radiating from a central point, with amethyst purple at some of the tips and cool mint green asagiite in mostly log-shaped crystals, with a few blobby bits.

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Quartz'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.
Mineral Cup #MinCup@MineralCupSep 6
#MinCup26 Round 1 Match 6 It's a classic vs a newbie as the most common named mineral in the crust #Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago #Asagiite. VOTE: mineralcup.org/2026/vote-res… RESULTS: mineralcup.org/2026/vote-res…
Split photo of clear quartz points radiating from a central point, with amethyst purple at some of the tips and cool mint green asagiite in mostly log-shaped crystals, with a few blobby bits.

ALT Split photo of clear quartz points radiating from a central point, with amethyst purple at some of the tips and cool mint green asagiite in mostly log-shaped crystals, with a few blobby bits.

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