#MinCup25 has started and this year I am prepared to show to all my chemist colleagues, how cool minerals are 💪.
Kerstin Neuhaus
- 165 Followers
- 110 Following
- 1.3K Posts
mineralogist turned materials scientist (she/her) specialized in atomic force #microscopy #AFM & solid state ionics in oxides, loves 🌋, #minerals, planetology and good food, research group leader at @fzj, Team #MinCup25
How can we measure that? The answer is: with an adapted Hebb-Wagner-type measurement device. This means, we use ion blocking, but electron conducting contacts (Pt). On the backside, there is a large Pt sheet contact and on top is a small Pt micro contact (contact size reduces the polarization time).The micro contact is surrounded by dielectric paste, which shields the contact from inserting new oxygen or protons from the surrounding environment. The whole setup is placed in an oven.
Let's now come to the pyrochlores: our benchmark material La2Ce2O7 shows a pyrochlore structure, which is a relative of the #fluorite and bixbyite structure. The mineral pyrochlore is relatively common with an ideal composition of Ca2Nb2O7.
📷: Brown pyrochlore crystal, Rob Lavinsky, iRocks.com
#Quartz 🐯 as tiger eye modification shows chatoyancy, an effect that resembles cat's eyes. #MinCup23
So it's #quartz against #stibnite today in this second round of #MinCup23. For me, my decision is crystal clear: #Quartz for the win. These are stbnite and some quartz single crystal exhibits from the mineral collection at University of Münster.
Went for my Sunday morning run and the road was blocked by 20 m of ankle-deep mud from a blocked drainage channel. My running shoes are soiled. No way, I will not vote for that today (although the paw prints are adorable). Vote #zircon! #MinCup23
Sometimes the samples can be so clear that you could read through them. But mainly, #calcite can be found as small-grained constituent of limestone or sandstone.
Examples below (left is ca. 15 cm in height) from Mønsted Limestone Mines in Denmark, collected during this year's Summer vacation
Match 11 of #MinCup23 today and this will be a tough one: shiny mineraloid #opal against good, old bubbling #calcite. Opal has the looks but I prefer a crystal structure... See some fabulous examples of #calcite to convince you...
#Calcite can form very well-defined crystals but sometimes also looks a bit plain and beige. All samples from mineral exhibition at Uni Münster.
