Direct mineralogical imaging of economic ore and rock samples with multi-modal nonlinear optical microscopy

Mung Chung Kao, Adrian F. Pegoraro, David M. Kingston, Albert Stolow, Wen Chuan Kuo, Patrick H.J. Mercier, Ankur Gogoi*, Fu Jen Kao, Andrew Ridsdale

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


Multi-modal nonlinear optical (NLO) microscopy, including stimulated Raman scattering (SRS) and second harmonic generation (SHG), was used to directly image mineralogical features of economic ore and rock samples. In SRS/SHG imaging, ore samples generally require minimal preparation and may be rapidly imaged, even in their wet state. 3D structural details, at submicron resolution, are revealed tens of microns deep within samples. Standard mineral imaging based on scanning electron microscopy (SEM), with elemental analysis via energy dispersive X-Ray spectroscopy, was used to independently validate the mineral composition of the samples. Spatially-resolved SRS from dominant Raman-resonant bands precisely maps the locations of specific minerals contained within the samples. SHG imaging reveals locally non-centrosymmetric structures, such as quartz grains. Competing absorption and nonlinear scattering processes, however, can reduce contrast in SRS imaging. Importantly, the correlation between standard electron microscopy and multi-modal NLO optical microscopy shows that the latter offers rapid image contrast based on the mineral content of the sample.

Original languageEnglish
Article number16917
JournalScientific reports
Issue number1
StatePublished - 1 Dec 2018


Dive into the research topics of 'Direct mineralogical imaging of economic ore and rock samples with multi-modal nonlinear optical microscopy'. Together they form a unique fingerprint.

Cite this