Scientists Unravel Defect-Free Crystal Growth Courtesy of Dolomite

The iconic Dolomites form striking, jagged peaks across the northern Italian Alps. However, for two centuries, the mineral at the center of this mountain range — dolomite, CaMg(CO₃)₂ — has remained a mystery. While the material is abundant in ancient rock formations, younger deposits are rare. And, while most crystals grow in supersaturated solutions, dolomite does not readily grow at ambient conditions, even when highly supersaturated. This conundrum has left scientists perplexed about how dolomite forms and grows.

Now, the dolomite problem may have finally been solved by researchers at the Univ. of Michigan and Hokkaido Univ. The team has devised a breakthrough technique to synthesize dolomite in the laboratory, offering potential insights into creating crystals for applications such as batteries, solar panels, and even defect-free semiconductors.

“The question is not just what to make, but how to make it,” says corresponding author Wenhao Sun, Assistant Professor of Materials Science and Engineering at the Univ. of Michigan. “If we understand how dolomite grows in nature, we might learn new strategies to promote the crystal growth of modern technological materials.”

To unravel dolomite’s growth process, Sun and team first delved into the mineral’s atomic structure. They observed that the surface of mature dolomite exhibits perfectly alternating rows of calcium and magnesium ions. However, it is highly improbable that new dolomite initially forms in this pristine pattern, according to Sun. “In nature, there is something called entropy, and entropy makes things want to disorder,” he says.

In reality,...