AFTER the baby earthquakes two weeks ago in San Jose, it seemed serendipitous that the monthly meeting of the Santa Cruz Mineral and Gem Society was having a guest speaker from the U.S. Geological Survey—though after Haiti, "serendipitous" seemed entirely the wrong word. Nevertheless, the society met one night last week in the main room of the Masonic Temple on Branciforte. Seated at long tables, members peered through 3-D glasses at posters of famous rock formations. The society's fresh-faced president, 27-year-old Crystal Byler, gave the "Rock Star of the Month" award to a particularly industrious member and reminded everyone of their dues before the meeting broke for cookies and the raffle of "awesome rocks."

As three very businesslike teenagers pulled numbers from a bingo cage, Byler asked me, "Are you into rocks?" I had never seriously considered "rocks" as a thing you could be "into." This, apparently, is not an uncommon problem. Many similar clubs around California are facing the same fate as the snails encased in 450 million-year-old Wyoming oncolite and brought in by the USGS speaker. "There are a lot of other groups like this where the older people die off and there's no one left," said 85-year-old Marion Fowler, a tiny woman with bobbed silver hair. That didn't seem to be trouble here. Of the roughly 30 attendees, plenty were middle-aged, a handful were young, and—surprising to me at least—the women outnumbered the men. "Maybe that's the jewelry-making side of it. It's half art and half science," said Fowler, who falls on the science side. Her late husband, a geologist, started taking her to meetings; she still attends, even though he passed away three years ago. "Some of us are just hooked," she said.

"Oh, four, two!" one of the teenagers called impatiently for the fourth time as the winner rushed in from an adjacent room. "Well, I'm doing rock stuff over there," she said huffily. Finally the USGS speaker stood up and began his lecture. It should have been clear to me by then that we weren't going to talk about big-picture geologic stuff like deadly 7.0 quakes. We were there to discuss the rocks. "I love rocks because every rock has a story," began Phil Stoffer, a fossil expert with the agency, before explaining how the shifting ground produces all kinds of special rocks. "How a rock can go from the surface to 50 miles down and back to the surface is just mind-blowing. That's what I like about rocks."

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