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chemical substituents; it can be engineered to incorporate REEs,
making this material extremely useful as a functional material.
Their ability to be fabricated in thin films makes perovskites ideal
for solar photovoltaic cells (Fig. 6). Perovskite photovoltaics are
an emerging technology due to their high efficiencies for convert-
ing sunlight to energy. Recent advances to scaling up production
of these high-efficiency perovskite solar cell modules have intro-
duced organics into the perovskite precursor—allowing a uni-
form thin film to be deposited across the entire photovoltaic mod-
ule area (Huang et al., 2021).

Figure 7. Two representations of the analcime (NaAlSi 2 O 6 · H 2 O) structure,
down [111], showing the location of the ions, the channel structure, and sev-
eral bonds. Polyhedral model (left), ball and stick model (right). (Each repre-
sentation can be transformed into the other to enhance an ability to see in
Figure 6. Panel of solar 3D.) Such minerals have properties for superionic mobility of ions, needed for
photovoltaic cells at the renewable energy systems. See footnote 1 for a link to the animation.
GSA Headquarters in
Boulder, Colorado, USA;
used with permission. way, minerals are what make duct tape’s stickiness so special. It’s
Perovskite photovoltaics
potentially replace the stickiness is due to zinc—a chemical element extracted from the
more common silica- mineral sphalerite (ZnS).
based solar cells and
have a higher efficiency.
MINERALS ARE ESSENTIAL
Minerals are critically important for powering our future, and
mineralogical expertise is essential for unleashing their full poten-
tial. Knowing where to explore for specific mineral constituents
and how to protect the environment during extraction are para-
mount to safely securing critical minerals. Understanding minerals,
Minerals with a rigid structure and channels that are flexible at dif- crystal structures, structural constraints, elemental substitutions,
ferent pressures and temperatures are vital to new, improved func- and analytical techniques for analyses bridges the earth sciences to
tional materials. Such mineral properties allow for ionic to superionic other STEM disciplines and leads to computational and experimen-
mobility, which is critical for developing the next generation of solid- tal advances in new materials, patterned on natural minerals, as
state electrolytes, and power our transition toward a fully renewable resources for transitioning to a cleaner, renewable, energy future.
future. The feldspathoid analcime is one such mineral, with its channel When you turn on the lights, use your cell phone, or start the car,
structure and sodium atoms, and has an onset of super ionic conductiv- think of the minerals that underlie our technologically rich society
ity (D. Palmer, personal commun., 2021; Fig. 7 [see Supplemental and impact our daily lives. “We don’t buy minerals, we need their
Material ]). Zeolite minerals, which also have channel structures and constituents” (USGS, 2021). Today, the vastness of minerals essen-
1
flexible chemistry, have long been used as manufactured materials for tial to our technological lifestyles cannot be overstated. Let’s appre-
molecular sieving and catalysis. For a newer perspective in mineral sci- ciate minerals in all their scientific enormity.
ence, an inside view of a resource needed for transitioning to a renew- The time is now for minerals to move to the forefront as the
able energy future is shown in Figure 7 (and see footnote 1). Two crys- domain of earth sciences and for the geoscientists to embrace this
tal representations display the crystal structure showing the position of domain by teaching, learning, funding, exploring, and promoting
the ions, the channels, and many of the bonds at an atomic view. One an understanding of minerals for the future of society, as a techno-
can transform in your mind between the two crystal structure repre- logical imperative and as a scientific endeavor. Minerals matter!
sentations, as do our students, to improve the ability to see in 3D. Such
knowledge of minerals, their crystallography, and their thermody- ACKNOWLEDGMENTS
namic properties translates through technology and engineering and My appreciation to Darrell Henry, Nina Rosenberg, and Pamela Kempton for
leads to new advances for materials critical for saving planet Earth in a their thoughtful reviews, together with Wendy Bohrson, Dave Mogk, and many
new, Earth-forward perspective. other colleagues for unwavering support of this topic. To my many mineralogy
students over the years, who asked for more mineralogy classes and encouraged
DUCT TAPE my development of minerals in context, thank you. David Palmer of Crystal-
Maker (TR) is thanked for sharing his insights on superionic conductivity, for
These examples show that mineralogy is like duct tape—know- developing the powerful visualization program Crystalmaker, and for making
ing how to use it can solve many problems! Minerals can be part the animation (Fig. 7 [see footnote 1]). Mark Mauthner and Rob Sielecki gener-
of the solution for some of today’s stickiest challenges. By the ously provided photographs.

1 Supplemental Material. Animation flies through the mineral structure of analcime, a mineral with ionic to superionic conductivity. Structure is represented by a ball (show-
ing atoms) and stick (showing bonds) model. The beginning view is a “surface cell” perpendicular to the channel axis looking down <111> to view the pseudo-trigonal
representation. Channel axes is 273 Angstroms wide. First image is about 23 times the channel width or 1288 unit cells. Courtesy of David Palmer, CrystalMaker. Go to
https://doi.org/10.1130/GSAT.S.17320556 to access the supplemental material; contact editing@geosociety.org with any questions.

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