#GeoscienceBluesky
LightNews LightNews
andersonmineral.bsky.social
The metamorphic mineral staurolite with its distinctive penetration twinning forming a cross. It’s positively delightful!! #MineralMonday #GeoscienceBluesky ⚒️🧪
Brown crystals forming a cross in white matrix. It sits on a black background. At the Sorbonne.
November 10, 2025 at 12:23 PM
andersonmineral.bsky.social
Ah yes!! Another bacon specimen!! This time it’s banded aragonite. #MineralMonday #GeoscienceBluesky ⚒️🧪
Specimen that is a polished slab of white and pale and dark brownish pink stripes , resembling bacon. It sits on a grey background with the edges of another specimens and labels seen around it. Label to the bottom right says « D28 - BM.58818 Stalagmitic banded, polished Loket, Karlovarský kraj. Czech Republic » At the Natural History Museum London.
November 3, 2025 at 12:35 PM
andersonmineral.bsky.social
The answer is the iron ore hematite!! A streak is when you rub a mineral on a slightly rough surface to see what colour the powder left behind is. The streak helps identify the mineral, as it might be different than the colour of the specimen. #GuessTheGem #GeoscienceBluesky ⚒️🧪💎
andersonmineral.bsky.social Erika Anderson @andersonmineral.bsky.social · 14d
Another Tuesday Guess the Gem!! What mineral do you think these gems are? Hint: their streak would be red.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
In the center are two gems, each on white foam in a white gem case. The one on the left is a round cut and the right is a long cabochon with two pointed ends in the east west direction. They are surrounded by lined up gem cases you can see the edge of. At the Hunterian.
October 29, 2025 at 11:40 AM
andersonmineral.bsky.social
Another Tuesday Guess the Gem!! What mineral do you think these gems are? Hint: their streak would be red.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
In the center are two gems, each on white foam in a white gem case. The one on the left is a round cut and the right is a long cabochon with two pointed ends in the east west direction. They are surrounded by lined up gem cases you can see the edge of. At the Hunterian.
October 28, 2025 at 11:33 AM
andersonmineral.bsky.social
Another bright mineral!! The element sulphur makes these beautiful crystals. Be careful, sometimes the warmth of your hand can cause these sensitive crystals to crack. #MineralMonday #GeoscienceBluesky ⚒️🧪
Tall specimen consisting of many bright yellow sulphur crystals on grey matrix. It sits on a frosted plinth in front of a grey wall. An edge of another striped mineral, orpiment, can be seen at the top left. At the Royal Ontario Museum.
October 27, 2025 at 11:34 AM
andersonmineral.bsky.social
The answer to this Guess the Gem is peridot!! This is a variety of the mineral group olivine, frequently found in basalts (and found in some meteorites!). #GuessTheGem #GeoscienceBluesky ⚒️🧪💎
andersonmineral.bsky.social Erika Anderson @andersonmineral.bsky.social · 21d
Another Guess the Gem for you!! What mineral or variety do you think this gem is? Hint: this is the gem variety of a mineral commonly found in my favourite type of rock: volcanic.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Green irregular cut gem in a clear round gem case on beige foam. The case sits on a beige background. The top edge of a small white label can be seen on the bottom right. At the National Museum of Ireland.
October 22, 2025 at 11:16 AM
andersonmineral.bsky.social
Another Guess the Gem for you!! What mineral or variety do you think this gem is? Hint: this is the gem variety of a mineral commonly found in my favourite type of rock: volcanic.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Green irregular cut gem in a clear round gem case on beige foam. The case sits on a beige background. The top edge of a small white label can be seen on the bottom right. At the National Museum of Ireland.
October 21, 2025 at 11:32 AM
andersonmineral.bsky.social
The most delectable rhodochrosite!! Bright minerals make me very happy!! From bright butterfly wings to the plumage of birds of paradise, nature is a tapestry of rich colours. #MineralMonday #GeoscienceBluesky ⚒️🧪
Specimen showing large bright reddish pink rhombohedrons with small white to clear crystals of quartz on dark grey matrix. It sits on a frosted plinth in front of a grey wall. At the Royal Ontario Museum.
October 20, 2025 at 11:26 AM
andersonmineral.bsky.social
The answer is tanzanite!! It’s a mineral only found in one area of Tanzania and it shows trichroism.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
andersonmineral.bsky.social Erika Anderson @andersonmineral.bsky.social · 28d
Another Guess the Gem for this week!! What mineral do you think these gems are? Hint: its colour depends on which side of the crystal you are looking at.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Two gems in white plastic gem cases on white foam surrounded by the edges of other gem cases. The left gem is greyish blue oval-ish cut and the right is a dark purple blue rectangular-ish cut. At the Hunterian.
October 15, 2025 at 11:34 AM
andersonmineral.bsky.social
Another Guess the Gem for this week!! What mineral do you think these gems are? Hint: its colour depends on which side of the crystal you are looking at.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Two gems in white plastic gem cases on white foam surrounded by the edges of other gem cases. The left gem is greyish blue oval-ish cut and the right is a dark purple blue rectangular-ish cut. At the Hunterian.
October 14, 2025 at 11:25 AM
andersonmineral.bsky.social
Some beautiful spherical ferrian turquoise, also known by the variety names henwoodite or rashleighite. #MineralMonday #GeoscienceBluesky ⚒️🧪
Small spheres of bright turquoise turquoise on dark brown matrix in cavities of a rust coloured rock. It sits mounted on a black shelf. At the Sedgwick Museum.
October 13, 2025 at 12:25 PM
andersonmineral.bsky.social
The answer is diopside!! Asterism is when inclusions (or sometimes twinning) cause refraction or reflection to concentrate light into a star shape. #GuessTheGem #GeoscienceBluesky ⚒️🧪💎
andersonmineral.bsky.social Erika Anderson @andersonmineral.bsky.social · Oct 7
Guess the Gem time!! What mineral do you think this gem with asterism is? Hint: sometimes called jasper or emerald, it is a different mineral.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Black sphere showing a white 4 rayed star (asterism) slightly off centre to the lower left. It sits on a frosted plinth with a number 4 on it. It sits on a grey background with the bottom of another plinth showing behind it. At the Royal Ontario Museum
October 8, 2025 at 11:26 AM
andersonmineral.bsky.social
Guess the Gem time!! What mineral do you think this gem with asterism is? Hint: sometimes called jasper or emerald, it is a different mineral.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Black sphere showing a white 4 rayed star (asterism) slightly off centre to the lower left. It sits on a frosted plinth with a number 4 on it. It sits on a grey background with the bottom of another plinth showing behind it. At the Royal Ontario Museum
October 7, 2025 at 11:31 AM
andersonmineral.bsky.social
It’s Geodiversity Day & Mineral Monday!! So I wanted to show you a rare mineral called carletonite, which is usually bright blue but seen here with a pink zonation. It was discovered here in Canada, at the mineral species rich Mont Saint-Hilaire. #GeodiversityDay #MineralMonday #GeoscienceBluesky ⚒️🧪
Specimen of carletonite with prisms of blue and pink all around. There is one large square crystal with a small blue square in the middle with pink on the outside on the upper right side of the specimen. It sits on a black background. At the Canadian Museum of Nature.
October 6, 2025 at 11:18 AM
andersonmineral.bsky.social
If you like colourful minerals, check out crocoite!! #MineralMonday #GeoscienceBluesky ⚒️🧪
Specimen consisting of many long tabular crystals of bright orange crocoite at various different angles on a black shelf. At the Canadian Museum of Nature.
September 29, 2025 at 11:43 AM
andersonmineral.bsky.social
This chalcedony is so beautiful!! It looks like a modern art sculpture or something swept up in the wind. How does this form? #MineralMonday #GeoscienceBluesky ⚒️🧪
White chalcedony made up of the rounded long lengths resembling thick fibres making it look like a wad of string or cloth falling apart. Label on the bottom says “Chalcedony/SiO2/Locality Unknown”. At the Sedgwick Museum.
September 22, 2025 at 11:33 AM
andersonmineral.bsky.social
One of the coolest hematite specimens I have ever seen, it’s wider than my hand!! It’s from Parkside, Cumbria, UK. #MineralMonday #GeoscienceBluesky ⚒️🧪
Specimen of hematite that is made up of round concentric segments that form donut shapes stacked on top of one another (3-4). Looks a bit like curled up pull bugs. It sits on a black shelf with the edge dark grey specimen seen next to it. At the Great North Museum: Hancock.
September 15, 2025 at 8:33 AM
andersonmineral.bsky.social
Take a pause from the stress in choosing your votes for Mineral Cup and refresh your palate with this fluorescent bright orange coral-like halite. Minerals are just so cool. #MineralMonday #GeoscienceBluesky #MinCup25 ⚒️🧪
Specimen made up of many small cubes making branches off a base. The specimen is fluorescing orange with a black background. At the Royal Ontario Museum.
September 8, 2025 at 9:24 AM
andersonmineral.bsky.social
The answer is last year’s Mineral Cup winner: rhodochrosite!! Best of luck to all the mineral candidates this year!! #GuessTheGem #GeoscienceBluesky #MinCup25 ⚒️🧪💎
andersonmineral.bsky.social Erika Anderson @andersonmineral.bsky.social · Sep 2
Guess the Gem time!! What mineral do you think this gem is? Hint: last year’s winner.
#GuessTheGem #GeoscienceBluesky #MinCup25 ⚒️🧪💎
Bright pink rectangular scissor cut gem on a white background. At the Canadian Museum of Nature.
September 3, 2025 at 11:09 AM
andersonmineral.bsky.social
Guess the Gem time!! What mineral do you think this gem is? Hint: last year’s winner.
#GuessTheGem #GeoscienceBluesky #MinCup25 ⚒️🧪💎
Bright pink rectangular scissor cut gem on a white background. At the Canadian Museum of Nature.
September 2, 2025 at 11:02 AM
andersonmineral.bsky.social
Bright green pyromorphite from Broken Hill Mine, Zambia. Love seeing bright coloured minerals!!! #MineralMonday #GeoscienceBluesky ⚒️🧪
Specimen with small crystals of bright green pyromorphite on dark grey and brown matrix. It sits on a black shelf and a black background with a small white square label with 7 on it. At the Hunterian.
September 1, 2025 at 12:18 PM
andersonmineral.bsky.social
The answer is scapolite!! The name for this mineral group comes from Greek words for rod and stone. #GuessTheGem #GeoscienceBluesky ⚒️🧪💎
andersonmineral.bsky.social Erika Anderson @andersonmineral.bsky.social · Aug 26
Another Guess the Gem!! What mineral group do you think these gems are? Hint: they are “rod”s in the “stone”.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Two colourless gems in gem white gems boxes on white foam, surrounded by the edges of gem boxes. Top gem is oval and the bottom is a baguette, long and thin. At the Hunterian.
August 27, 2025 at 10:54 AM
andersonmineral.bsky.social
Another Guess the Gem!! What mineral group do you think these gems are? Hint: they are “rod”s in the “stone”.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Two colourless gems in gem white gems boxes on white foam, surrounded by the edges of gem boxes. Top gem is oval and the bottom is a baguette, long and thin. At the Hunterian.
August 26, 2025 at 11:11 AM
andersonmineral.bsky.social
The answer to this one is tourmaline!! It’s a mineral group that has a variety of colours, some crystals even have multiple colours. #GuessTheGem #GeoscienceBluesky ⚒️🧪💎
andersonmineral.bsky.social Erika Anderson @andersonmineral.bsky.social · Aug 19
Guess the Gem time!! What mineral group do you think these gems are? Hint: there are A LOT of mineral species in this group.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Five gems on cream foam in round transparent plastic gem cases with no lids. Top left is rectangular dark green. Top right is rectangular with cut corner and pink. Middle left is rectangular with rounded edges and dark blue green. Middle right is a bit rounder dark yellow brown. Bottom is a square cut with small rounded corners and very dark green. At the bottom right is a small white square label with 3 on it. All sits on a cream background. At the National Museum of Ireland.
August 20, 2025 at 10:51 AM
andersonmineral.bsky.social
Guess the Gem time!! What mineral group do you think these gems are? Hint: there are A LOT of mineral species in this group.
#GuessTheGem #GeoscienceBluesky ⚒️🧪💎
Five gems on cream foam in round transparent plastic gem cases with no lids. Top left is rectangular dark green. Top right is rectangular with cut corner and pink. Middle left is rectangular with rounded edges and dark blue green. Middle right is a bit rounder dark yellow brown. Bottom is a square cut with small rounded corners and very dark green. At the bottom right is a small white square label with 3 on it. All sits on a cream background. At the National Museum of Ireland.
August 19, 2025 at 10:42 AM