The samples contained a high proportion of kaolinite, the fine-grained mineral Owen had suspected when he rubbed the pale mud between his fingertips. Several measures of brightness and iron content were unusually favorable, especially in the sample nearest the old capture chamber. Additional tests were still required to understand trace elements, moisture, consistency, and how the material behaved when processed, but the initial composition was sufficiently distinctive that the university laboratory had repeated part of the analysis before releasing it. They wanted to be certain they had not confused a sampling anomaly with a deposit.
"How valuable?" Adele asked. Owen was quiet for a beat, and she knew she had asked the question everyone would ask first. "It is potentially valuable, depending on how much is there and whether it can be recovered without destroying the spring," he replied.
"High-purity kaolin can serve specialized ceramic markets, and material meeting much stricter specifications can be used in certain cosmetic or pharmaceutical processes. We're nowhere near certifying those uses yet. What we have established is that this isn't ordinary pond clay."
Adele leaned against the counter and looked at the small wet patch her boot had left on the floor. For weeks she had been paying to investigate an unpleasant smell and a warning in her husband's old notebook. Now a scientist was telling her that the pale layer she had noticed in the first two hours might have commercial value precisely because it was unusually clean. She asked him to send the report and explain each figure when he visited, because she did not want to carry a conclusion she could not understand. Owen seemed delighted rather than offended by the request.
He arrived the following afternoon with a portfolio of diagrams and a bag of small sample containers. They sat at the kitchen table where Adele had once sorted Tobias's homework, and Owen explained the results without hurrying. He showed her the mineral identification, the comparative measurements from the southern and northern samples, and a map illustrating how the pale material appeared to follow the old subsurface flow path. The preliminary evidence suggested a natural clay body had formed through very long weathering of the ridge rock and that the hydraulic system might have helped keep parts of it free from contamination by iron-rich surface runoff.