#MinCup24 R2M4: #Dioptase versus #Vivianite

Dioptase is rare and has glorious emerald to teal-green vitreous and translucent crystals. Vivianite can grow on decaying wood, bones and other organic material, much to gothic delight.

If this match feels familiar, we saw this same battle in Round 2 Match 3 of Mineral Cup 2023. But every year are new voters with new motivations! Which will you choose this year?

VOTE: https://www.mineralcup.org/2024/vote/r2m4

⚒️🧪 geology

After a close race that flipped back and forth many times over, congratulations to #Dioptase the Desert Emerald for making it into #MinCup23 Round 3!

Better luck next year to the spooky yet charming #Vivianite

#Vivianite growing in the pore spaces of bones from a 4000 year-old tomb in Sardinia (Rodriguez et al. (2021) J. Arch. Sci. Reports). Phosphate bones plus dissolved iron equals vivianite. #MinCup24 #Archeology

There was a very interesting essay on #vivianite in Nature Geoscience recently (Slomp 2023). Vivianite could be used to trap excess P in wastewater, preventing it from causing environmental damage in coastal areas, thereby improving water quality for marine creatures. Vivianite formed in wastewater could be extracted and used in agriculture, “nicely closing the terrestrial phosphorus cycle”. Minerals saving the world! #MinCup23

A Scientific Study of the Absorption of Evil by Vivianite
By Alfred Petrov 2006
#MinCup23 #Vivianite

https://www.mindat.org/article.php/137/A+Scientific+Study+of+the+Absorption+of+Evil+by+Vivianite

#Vivianite I had to look up last year. It is a blue-green hydrated iron phosphate (Fe2(+II)[PO4]2 x 8H2O) with monoclinic crystal structure and acicular or fibrous aggregates.

But look at this 🤩: #Vivianite pseudomorph after shell from Kerch, Crimean Peninsula, Ukraine (size: 5.6 × 4.6 × 2.7 cm). #MinCup23

📷 Rob Lavinsky, iRocks.com

Ready for a pair of rare and delicate beauties in #MinCup23 Round 1 Match 7?

It’s ever-darkening #Vivianite vs vanadium-blue #Cavansite!

Vote: https://www.mineralcup.org/2023/campaigns/round-1-match-7

Results: https://www.mineralcup.org/results/round-1-match-7