Hazel-Atlas Mine Tour

My husband and I signed up for the new extended Hazel-Atlas mine tour at Black Diamond Mines, and met our tour group at the Greathouse Portal. It was 90 degrees outside, but we felt refreshing cool air coming through the portal from deep inside the hill.

The Greathouse Portal - original entrance to the sand mine

The Greathouse Visitor Center

Warren of mine shafts

After an introduction, we hiked about 15 minutes to the Hazel Atlas Portal, and the gated entrance to the Eureka Coal Mine. We learned about coal (the pressurized remains of peat from a vast inland sea), and the coal mining that took place from 1860 -1906 (miners came from all over the world, conditions were hard, and the hours long). Mining was finally stopped because the Mount Diablo Coalfield produced the lowest grade of coal, lignite.

The Eureka Slope - entrance to the Eureka Coal Mine

Eureka Coal Mine

We suited up with our hard hats and LED flashlights and hit the mines. We saw the office, where all workers and visitors checked in for safety. Everyone had to be accounted for in case of an accident in the mine.

Suited up and ready to tour

The office

Veins of coal running through sandstone

Sand mining took place from 1920s -1940s. The sandstone produced silica that was almost 95% pure. It was used by the Hazel-Atlas Glass Company to manufacture bottles and jars in Oakland. The sand is very fine, so easy to see why it was selected for making glass.

Vein of coal running through the sandstone

A chute for loading ore cars with sand

A giant stope left from mining sand

On the tour we saw cutaways of the veins of coal running through the sandstone. We also saw an earthquake fault which was interesting (and sobering). We were grateful for all the rock bolts and special steel-frames protecting the passages. Our tour guide pointed out stopes and chutes, and a mine car filled with sand.

Back at the Visitor Center we learned more about glass production.

Ore car filled with sand	Form for an Atlas-Mason jar
Formed shot glass and jar	Collection of glass products

We finished the tour at the small gift shop, perfect for "Black Diamond" coal specimens, pencils, and black licorice "coal". We finished the day with dinner and conversation  at Casa Orinda Restaurant, an original roadhouse known for fried chicken and biscuits and many other delicious menu items.

This is a wonderful tour for anyone interested in geology, mining, or history. You can order tickets online, or buy them at the Greathouse Visitor Center (tours are small, so can sell out quickly).

Black Diamond Mines Regional Preserve

The hills around Black Diamond Mine Regional Preserve are hollow, with a warren of mine shafts running through them. I've been reading about its coal and sand mines for the last year, and wanted to see it for myself. My husband and I made a late summer excursion from the East Bay out to Antioch to visit this East Bay regional park.

Back Diamond Mine Regional Preserve

Monument to the Mount Diablo Coalfield near Antioch

Black Diamond Mines Regional Preserve is the site of the former Somersville mining town, which supplied glass-making sand to the Hazel-Atlas Glass Company in Oakland, as well as the townsites of nearby Nortonville, Stewartville, Judsonville, and West Hartley. From the mid-1800s to mid-1900s, this was a bustling mining area, which extracted nearly 4 million tons of coal and 1.8 million tons of sand.

View of the Somersville townsite, and the Rose Hill Cemetery on the hill

There is no trace of the former townsite, but the historic Rose Hill Cemetery remains high on the hill (you can spot it via the row of yews that seem out of place in the landscape). I confess we chose to sit in the shade, rather than trek up the hill in 90 degree heat, but maybe next time. As is characteristic of old California mining towns, the buildings were dismantled when a mine is closed, and the wood moved to the next mining site.

Ample picnic area

Shady picnic site

We allowed plenty of time for a picnic under the deep shade of the native oak trees. Mixed in with the native trees, we could see some of the exotic trees that had been planted by the miners, such as black locust, pepper, almond,  eucalyptus, and trees of heaven. The Black Diamond Mines brochure also notes that the park is the northernmost location for Coulter pine, black sage, desert olive, and dudleya. Quite a mix!

Some of these trees may have been planted by miners

View to "the Delta" in the distance

You'll find plenty of trails in the area for hiking and exploring. From one of the trails we could see a view through Markley Canyon clear to the Delta in the distance. I've been hearing about "the Delta" for years, and was glad to finally see a glimpse of it!

Mine tailings

I recommend the Black Diamond Mines Regional Preserve for anyone who loves the California landscape, with a dose of early California history thrown in. The hills are a great place to see wildlife and birds, and reportedly springtime flower displays. I also recommend taking a tour of the Hazel-Atlas Mine.

Fall at Bishop Ranch

Fall kicks off at Bishop Ranch with 80 to 90 degree days that could easily pass for summer just about anywhere else. Thankfully, the evenings cool off quickly due to shorter days and the coastal breeze that comes through the Hayward Pass each evening.

Fall leaves and summer flowering trees

The landscape at Bishop Ranch is conflicted – the leaves of the Liquid Amber trees are turning red, while the Crepe Myrtle trees still have blossoms in shades of pink and lilac.

A heron roosts in bare branches

Bright fall day

The baby geese and ducks have all moved on, but herons and Canadian geese still stop by the lake for a quick meal, or to roost in the trees. Shrubs and grasses that line Bishop Lake have gone to seed. I've collected a few seeds, and am curious if they are viable.

The red leaves deepen in color as fall progresses

The Bishop Ranch landscaping crew has been working on special projects, like planting a new bank of rosemary (Rosmarinus officinalis), and trimming the grass clumps to foster growth in the next season.

Grasses in bloom	Grasses cut back for fall
Crepe Myrtle seed pods	A young heron lake side

Fellow co-workers still take walks around the lake and grounds, but often later in the day when it is cooler. Soon enough, the hot days will give way to cool fall days, fabulous sunsets, bare branches, and the discreet fall colors of the Mediterranean climate.

Early sun sets in fall