New Almaden Mines

06/07/2026

Just an FYI for those that may be interested.

The next monthly Zoom (virtual web based) meeting for the informal New Almaden History Discussion Group will be Tuesday, June 9, 2026, at 7 pm. The Zoom login information is below.

For this meeting we will discuss the geology of the mine, the relationship of the ore to the rocks and to the mine workings. We will also have a round table if anyone has historical goings on to report.

Michael Cox is inviting you to a scheduled Zoom meeting.
Topic: New Almaden History Discussion Group
Join Zoom Meeting
https://us02web.zoom.us/j/83120987234...
Meeting ID: 831 2098 7234
Passcode: 2026
Meeting chat link
https://us02web.zoom.us/launch/jc/83120987234
Join instructions
https://us02web.zoom.us/meetings/83120987234/invitations...

Hope to see some of you on Tuesday.

Mike

05/23/2026

Close up of a gorgeous worn boulder of banded quartz and dolomite throwing off a purple fluorescence under long-wave UV even in daylight. Location undisclosed and boulder left alone. No rock molesting allowed! Chuckle.

P.S. - these banded veins form on the walls of active faults where gaps open up. Mineral laden waters deposit successive bands of quartz and dolomite. If the fault moves (earthquake) the host rock and banding can get broken up. It's called brecciation.

The boulder preserves a well-banded layer enveloped in earthquake breccia. The rock on either side of the fracture can be broken up and incorporated into the vein rock as it forms. If the host weathers away more quickly, the exposed faces get pits. If the host rock weathers more slowly than the vein material, the fragments will stick out.

In this example the pits hold water and the rock fragments are dissolving away. The fragments have more nutrients as compared to the banded quartz and dolomite, so moss and lichen inhabit the pits and make them more pronounced over time. Moss and lichen eat rocks? Well, sort of. Lichens actively dissolve rock by secreting organic acids, freeing up nutrients from the broken down minerals of the rock. Moss relies on moisture retention and mechanical expansion.

05/09/2026

Advocacy alert - CLICK THE LINK AND WRITE AN EMAIL NOW!! Save the SJ Public Library California Room https://www.preservation.org/california-room

Monday May 11th the Council will debate a budget that permanently closes a vital resource for research across a diverse range of fields, including open space, environment, planning, industry, community, and social cohesion. The California Room is not dusty books and antique librarians, it is three information professionals keeping one of the leading collections of vital information regarding the events that bring us to our time.

PAC*SJ urges City Council to reconsider an alarming proposal in the City’s 2026-27 budget to close the Martin Luther King Library’s California Room and eliminate its three dedicated staff positions. Established in 1906 as the local history section of San Jose’s first public library, the Califo...