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Home > Search > Site Map > California > The California Stone Industry > California Stone Industry (historical account up to circa 1950) - Continued

California Stone Industry (historical account up to circa 1950)

Excerpts from

Geologic Guidebook of the San Francisco Bay Counties:
History, Landscape, Geology, Fossils, Minerals, Industry,
and Routes to Travel, Bulletin 154

Olaf P. Jenkins, Chief, California Division of Mines,
San Francisco, California, December, 1951.


(Please note: Use the drop down box below to jump to the individual sections of this document.)

Volcanic Rocks Useful in the San Francisco Bay Area (Continued)

"Leona rhyolite occurs in a belt along the west flank of the Berkeley Hills from the vicinity of Claremont Canyon through Leona Heights to Decoto. When fresh, the rock is light bluish green in color, contains scattered phenocrysts, and in places contains pyrite. Where abundant enough to form ore bodies, the pyrite was mined for conversion to sulfuric acid. Leona rhyolite is probably Pliocene in age.

"A number of small, isolated patches of rhyolite are scattered along the front of the Berkeley Hills from North Berkeley to Richmond. They are remnants of a flow which, for the most part, has been removed by erosion. Rhyolite from these remnants differs from the Leona rhyolite in that the rock is less uniform, is commonly flow banded, and in places is glassy; pyrite is rare. The rhyolite in this group of occurrences has been named the Northbrae rhyolite; it is late Pliocene in age.

"Andesite and basalt, together with associated tuffs, are exposed in road cuts along Grizzly Peak Boulevard and along trails through the Berkeley Hills behind the University of California, as at Bald Peak. There are two series of these volcanic rocks, one lying stratigraphically above the other but separated from it by lake-bed sediments.

Fig. 6. Bennett Mountain, five miles southeast of Santa Rosa, Sonoma County. West limb of a syncline made up of east-dipping flows of adesite, basalt, ryholite, perlite, and beds of breccia, agglomerate, and tuff. Bennett Mountain, five miles southeast of Santa Rosa, Sonoma County
Fig. 7. Holt wine cellar on Holt Ranch, east of St. Helena, Napa County. Constructed in 1896 of perlite rock from quarry near site of cellar. Holt wine cellar on Holt Ranch, east of St. Helena, Napa County
Fig. 8. Baker Street, San Francisco. Looking south from Vallejo Street. Pavement made of basaltic paving cobbles. Baker Street, San Francisco
Fig. 9. Old St. Helena Winery, St. Helena, Napa County. Built in 1880 of rhyolite, andesite, and dacite. Old St. Helena Winery, St. Helena, Napa County

"The lower series, here designated the Grizzly Peak volcanics, lies above conglomerate, gravel, and clay of the Orinda formation of lower Pliocene age. The most interesting member of this series is a dense, dark-colored, amygdaloidal andesite containing large chalcedony amygdules or cavity fillings. The centers of some of these chalcedony amygdules may be hollow, the hollow being lined with quartz crystals to which may be attached crystals of calcite, natrolite, and analcite. Opal may be present either in amygdules or as fracture fillings. Above the amygdaloidal and andesite is a group of flows of andesite and basalt interstratified with rhyolite and basalt tuffs and some gravel. Topping the heterogeneous assemblage just described is massive flow andesite which is in part predominantly crystalline and in part porphyritic with a glassy groundmass. Some coarse breccia is interbedded with the massive andesites.

"The upper lava series, here called Bald Peak volcanics, lies on light-colored lake-bed shale, sandstone, clay, limestone, and chert of the Siesta formation of Pliocene age; these sediments in turn lie on the lower volcanic series previously described. The upper series consists largely of basalt flows. Basalt Specimens are porphyritic, the phenocrysts being predominantly plagioclase, feldspar, and olivine.

"Sonoma volcanics occupy extensive areas in Napa, Solano, and Sonoma Counties, and smaller areas in Marin County. They consist of lava, tuff, agglomerate, and breccia, which are predominantly andesite in composition but which include flows of perlite, rhyolite, dacite, and basalt; also present are various pyroclastic equivalents of these lava types. The Sonoma volcanics accumulated in a basin approximately 30 miles wide, which extended northwestward from Suisun Bay to the vicinity of Healdsburg, a distance of 50 miles.

"The best sections of Sonoma volcanic rocks occur in the vicinity of Penngrove and Burdell Mountain; in the Sonoma Mountains; on the west slope of the Mayacmas Mountains; in Napa Valley; and in the Howell Mountains. They reach their maximum thickness of about 2000 feet near the crest of the Mayacmas Mountains. The lavas are commonly flat lying or nearly so but may be inclined as much as 30 degrees.

"A prominent upper member of the Sonoma volcanics is called the St. Helena rhyolite. It forms conspicuous outcrops on Mount St. Helena as well as in most areas where Sonoma volcanics occur. Once considered to by trachyte, the member is now known to be largely rhyolite. The rock is coarse grained, bluish gray to white, and porphyritic; phenocrysts are sanidine, albite, oligoclase, and quartz; the groundmass is largely feldspar and quartz. In some places the rock is glassy and may grade into vitrophyre, perlite, or obsidian; flow banding is common, and multicolored, well-banded varieties have been extensively quarried for flagstone.

"A very unusual variety of rhyolite occurs in the Sonoma volcanics east of Petaluma and east of Glen Ellen. It contains the bluish-black soda-amphibole, riebeckite, which has an intense blue color in thin section, and is a very beautiful mineral. East of Glen Ellen, extensive flows of riebeckite rhyolite extend along the west side of the Mayacmas Mountains, from the Valley of the Moon quarry to Santa Rosa Canyon. The rock varies considerably in character between these two places. At the Valley of the Moon quarry, where the riebeckite rhyolite is being quarried for building stone and flagstone, the rock is bluish-gray, banded, vesicular, and granular. Specimens are porphyritic, and contain phenocrysts of sanidine, albite, and quartz set in a microcystalline aggregate of quartz and feldspar. Scattered through the rock are numerous small, black, needle-like crystals of riebeckite and stumpy prismatic crystals of aegirite, a soda-bearing pyroxene.

"Farther north riebeckite rhyolite grades into dense rock. In Sonoma Canyon, about a quarter of a mile below the Golden Bear Lodge, it occurs in a flow which dips steeply toward the west. At the top of the flow the rock is dense and bluish-gray; but it grades downward to dark greenish-gray at the bottom. Throughout the flow it is porphyritic and contains phenocrysts of quartz, sanidine, and riebeckite enclosed in a dense groundmass of quartz and feldspar. No attempt has been made to quarry the rock in this locality; however, andesite which lies below the rhyolite was extensively quarried in a small hill on the southwest side of Sugarloaf Ridge.

Fig. 10. Riebeckite rhyolite in the Valley of the Moon flagstone quarry, northeast of Glen Ellen, Sonoma County. Flow banding and jointing are parallel. Riebeckite rhyolite in the Valley of the Moon flagstone quarry, northeast of Glen Ellen, Sonoma County
Fig. 11. Holt Perlite rock quarry, Holt Ranch east of St. Helena, Napa County. Not columnar jointing. Holt Perlite rock quarry, Holt Ranch east of St. Helena, Napa County
Fig. 12. J.M. Nelson quarry, near Cordelia, Solano County. General view of crushing and screening plant and stock pile of crushed basalt. J.M. Nelson quarry, near Cordelia, Solano County
Fig. 13. J.M. Nelson quarry. Rock is olivine basalt in flat-lying flows associated with tuffs and breccia. The basalt is now being quarried for crushed rock. Formerly used in making paving blocks. J.M. Nelson quarry

"Perlite is another of the Sonoma volcanics which deserves special mention because of its present economic importance to the building industry. It occurs in flows and irregular lens-like bodies, associated with tuffs and other varieties of volcanic rocks; perlite flows may contain obsidian. There are numerous perlite flows southeast of St. Helena and on Taylor and Bennett Mountains southeast of Santa Rosa.

"The Putnam Peak basalt occurs 6 miles northwest of Vacaville, on Putnam Peak in Solano County. The rock, which is in isolated patches, is dark and dense, and is vesicular near the upper surface of the flow; it contains phenocrysts of labradorite, augite, and olivine set in a microcrystalline groundmass of augite and feldspar. The dark color results mainly from small grains of magnetite which are scattered through the groundmass.

"The Putnam Peak basalt represents fissure outpourings of lava more or less contemporaneous in age with parts of the Sonoma volcanics.

"Source of Volcanic Rocks. Very little is known about the sources of volcanic rocks found in the San Francisco Bay area. A casual glance at a few of the more prominent peaks, such as Mount Diablo, Mount Tamalpais, Mount St. Helena, and Hood Mountain, might suggest that they are extinct volcanic cones and craters which at one time expelled tremendous volumes of volcanic ash and pumice and extensive lava flows. This, however, is not the case. Mount Diablo is made up of Franciscan, Cretaceous, and Tertiary sedimentary rocks and attained its elevation through mountain-building processes which involved faulting and folding, and not volcanism. Mount Tamalpais for the most part is made up of Franciscan sandstone, shale, and chert. Mount St. Helena is made up of volcanic and sedimentary rocks. True, it resembles an extinct volcano, but it too owes its elevation to mountain-building processes rather than volcanic activity around some central vent. Those who have made the pleasant drive along Highway 29 between Sonoma and Santa Rosa have undoubtedly observed a conspicuous peak rising abruptly on the east side of the valley a few miles north of Kenwood. This peak, known as Mount Hood, could very easily be mistaken for an extinct volcano. Detailed geologic mapping of this mountain and the surrounding country indicates that it is made up of a series of lavas, breccias, and agglomerates that dip steeply westward. These volcanic rocks rest uncomformably upon Franciscan serpentine, and were probably expelled from fissure-like vents nearby. It has been suggested that Taylor Mountain might have been a source for some of the volcanic material in that part of the area, but not enough detailed geologic mapping has been done to substantiate this view.

"In all probability, most of the volcanic rocks in the San Francisco Bay area came from fissure-like vents which are now covered by volcanic debris. Some of these vents might well be located in the northern Mayacmas Mountains southeast of Mount St. Helena, where considerable amounts of andesitic agglomerate and breccia are exposed. Similar agglomerates and breccias are exposed along Sugarloaf Ridge east of Kenwood, and there is a possibility that these fragmental volcanic rocks occupy the position of former fissure-like vents. The tuffs in the Merced (upper Pliocene) formation at Lake Merced in southwestern San Francisco, and other tuffaceous deposits in the Berkeley Hills, probably derived their materials from vents north of San Francisco Bay.

"Utilization of Volcanic Rocks. Prior to the advent of the automobile, the bulk of the volcanic rocks quarried in the San Francisco Bay area - especially andesite and basalt - went into paving blocks for the streets of San Francisco and other thriving communities. From 1887 to 1913 at least 136 million paving blocks, valued at $5,712,000 were produced from numerous quarries in Marin, Napa, Solano, and Sonoma Counties. However, as the use of the automobile increased, a need for smoother streets arose, and there was a sudden decline in the paving-block industry and an increase in the production of crushed rock for macadamized roads.

"Many of the streets in San Francisco are still made of paving blocks, especially those on steep hillsides such as Broadway, between Leavenworth and Taylor, and Sanchez, between 18th and 19th.

"Volcanic rocks were also used for curb and foundation stones. Considerable quantities of basalt and andesite were crushed in the early days for concrete aggregate and road metal. The Petaluma rock quarry supplied crushed rock (andesite) for the state Highway near Ukiah in 1913.

"Some of the volcanic tuffs, particularly the compacted varieties, were quarried for building purposes, especially for public buildings and bridges in the counties north of San Francisco Bay. The material used consisted of andesite, dacite, rhyolite, and perlite.

"A few deposits of rhyolite were quarried for flagstone and building stone. Minor amounts of loosely consolidated rhyolitic tuff were ground for abrasive purposes. Pumicite, a volcanic ash, was mined near Calistoga and sold under the name 'Callustro' for polishing. The largest amount of pumicite used for abrasive purposes came from deposits in the Merced formation near Lake Merced, San Francisco.

"By 1913 approximately 74 quarries were in operation in the San Francisco Bay area. Of these, 43 percent produced paving blocks; 30 percent, building blocks; 25 percent, crushed stone used for concrete and road metal; and 2 percent, abrasives including ground pumicite.

"The present (circa 1950) uses of volcanic rocks in the San Francisco Bay area are rapidly changing to meet the demands for new products in construction and industry. Many of the old quarries that once produced paving blocks are now overgrown with trees and creeping vines. Some of these quarries, however, that are favorably located with regard to transportation, are currently producing crushed stone for concrete aggregate and road metal. Quarries in volcanic tuffs that formerly produced building blocks are now furnishing tremendous quantities of pumice for lightweight aggregate. Flagstones, building stones, and decorative stones are finding widespread use in the building industry. Quarries in rhyolite in Sonoma Valley are probably as active today (circa 1950) as they were in any preceding period.

"A new volcanic rock industry has been developing since 1947 in the San Francisco Bay area - the expanding of perlite for lightweight aggregate. This industry is only in its infancy, but several perlite-expanding plants are already in operation. Plaster aggregate has been manufactured from perlite rock quarried on the Holt Ranch in Napa County, and from the C. M. K. Quinlan Ranch in Sonoma County. Other deposits of this material will undoubtedly be utilized in the future. the search for perlite has shown that the rhyolitic rocks in the San Francisco Bay area contain numerous large deposits of expansible perlite. Many of these deposits are favorably situated in regard to transportation to this rapidly growing consuming area.

"Expanded perlite is used principally for insulating and acoustical plaster, for soundproofing and insulating pre-cast wallboard, for an insulating medium without use of a binder, as in frozen food lockers, and for abrasives used in scouring soaps and cleansers. It is also used as a filler in paints and rubber, as a filter aid, as an absorbent material, as a soil conditioner, as an insecticide carrier, as poultry litter, as a catalytic carrier in chemical processes, and as raw material for the manufacture of rock wool."

The Building Stone and Aggregate Industry of the San Francisco Bay Counties, by Mort D. Turner, Assistant Mining Geologist, California State Division of Mines. (circa 1950)

"California has the largest commercial output of rock products of any of the 48 states. It is far ahead of any other state in production of sand and gravel, and ranks near the top in production of crushed and broken stone. Of the total rock products produced in the state about one-third comes from the San Francisco Bay counties.

"The term stone, in commercial usage, is applied to material quarried from larger masses of rock. The same material in place before being quarried, broken, or cut is called rock. In the industry, rock products have been divided by custom and usage into several categories based on size and shape of the particles and the nature of the processing they have undergone. Sand and gravel are natural detrital stone materials which usually require only sizing and washing before marketing; crushed stone is made from rock or gravel; dimension stones are blocks shaped to various degrees; aggregate is crushed stone, sand, or gravel used in such materials as concrete, macadam, plaster, terrazzo, road metal, and railroad ballast.

"Prior to 1850 very little stone was used for construction purposes in California. Owing to the great increase in population after 1850, however, permanent bridges, public buildings, and all-weather streets became more desirable, and a building-stone industry developed. Sandstone, basalt, granite, and marble were extensively mined for construction or paving purposes at various places in the bay counties prior to 1900. With the decline of the building-stone industry in the early nineteen hundreds, there was a contemporary rise of the production of aggregate because of the great increase in the use of concrete in construction and road building. At the present time (circa 1950), the stone industry is centered around production of aggregate in its various forms.

"Sedimentary, igneous, and metamorphic rocks are all mined and used by the building-stone and aggregate industry of the San Francisco Bay counties. Hardness, coherence, workability, chemical stability and color are the principal characteristics which govern the choice of a rock for a given purpose. The principal rock types quarried in the bay region are sandstone and crystalline limestone from the Franciscan formation of the Coast Ranges; basalt, andesite, and rhyolite from the Berkeley Hills; and granite from the Sierra Nevada foothills of Sacramento County. In addition, there are imports of slate from El Dorado County and eastern United States; granite from Fresno County, Georgia, and New England; marble from the eastern United States; and sandstone from Arizona.

"Because most rock products are low-cost commodities there must be a local source of supply. Short-haul traffic in aggregate in the bay area is the rule; long hauls are uncommon. Dimension stone, on the other hand, is shipped in from points as distant as New England, Georgia, and Europe largely because of long-established trade practices. Although many of the mining operations are large, continuous, and serve an extensive area, others are relatively small and operate intermittently to supply local needs. Some deposits have been worked only during the life as a single project, such as the construction of a large building, dam, or bridge.

"Building stone and aggregate are almost always mined by open-pit or quarry. Great care and intimate knowledge of the rock are necessary for efficient quarrying of building stone. After quarrying the stone is dressed to size and shape, and may be polished to enhance the beauty.

"The mining of aggregate must necessarily be simple to hold the cost down. Crushed stone is generally produced by running an open cut into a face of suitable rock. The rock is blasted down and transferred to large crushers by trucks, scrapers, or conveyor belts. After crushing it is usually screened, sometimes washed, and commonly stockpiled according to size. Sand and gravel are taken in much the same way except that most gavel banks are sufficiently unconsolidated to be dug with power excavators without blasting. In many plants oversize gravel is crushed and either sold separately or mixed with uncrushed material of the same size range.

"The construction industry in the San Francisco Bay counties has available an adequate supply of aggregate of various types. Aggregate is produced in all of the counties, and in more than half of them it has been the most valuable mineral product marketed during recent years.

"The first recorded development of the stone resources of California following the Gold Rush was in the foothills of the Sierra Nevada at Folsom, where granite was quarried for building purposes in 1856. The area remained one of the state's centers of granite production, and is still intermittently active (circa 1950). The heaviest and steadiest producer has been the Folsom State Prison where granite dimension stone, riprap, and crushed granite have been produced by prison labor for many years. Much of the granite dimension stone has gone into prison construction, but from 1888-90 Folsom Prison furnished the rock for the construction at Folsom of a dam, canal, and first electric-power plant in central California, riprap, rubble, and ballast from the prison quarry once were used extensively by the Southern Pacific Railroad. Sandstone from the Eocene Ione Formation was quarried north of the Cosumnes River near Michigan Bar at an early date. The building stone from this deposit was used in construction in Sacramento, but production ceased before 1890.

"Except for granite, quarried occasionally at Folsom prison, and some sand and gravel taken from the American River, there is no current production of dimension stone or aggregate from that part of the San Francisco Bay region that is within the Sierra Nevada province.

"Because of the lack of rock exposures in the Great Valley, that area is largely dependent for aggregate upon extensive deposits of alluvial sand and gravel. The need for crushed stone is supplied primarily by crushing gravel obtained locally, and in part by crushing stone obtained from quarries in the Coast Ranges. Large-scale production of aggregate in this area did not begin until 1900. In 1904 the total sand and gravel production for all of California was only 23,000 tons as compared with over 1,500,000 tons produced in Sacramento County alone in 1947.

"Sand and gravel obviously must consist of a wide variety of abrasion-resistant rock types. The first sources were pits dug in recently formed bar and channel deposits along streams flowing down from the Sierra Nevada. Gravel was removed by scrapers and drag lines. Older terrace gravels, which cover a large part of the valley, later became sources of sand and gravel, and still furnish most of the present production.

"One of the largest operations in the Great Valley is at Fair Oaks, Sacramento County, where coarse dredge tailings are washed, crushed, and graded. In 1920 the plant was leased to the Coast Rock and Gravel Company. In 1929 that company was consolidated with Pacific Coast Aggregates, Inc., which now operates the plant. Pacific Coast Aggregates at that time also absorbed the Pratt Building Materials Company at Mayhew and Rhodes, Jamieson and Company, both in Sacramento County, and the Associated Gravel Company at Riverbank, San Joaquin County. What is probably a unique method of recovering sand and gravel is the large-installed suction pump operated by Robert Powell and Company. The rig operates along the American River, lifting gravel from the river bed.

"Some of the large gravel pits most easily seen from the highway (circa 1950) in the Great Valley are those of the Perkins Gravel Company on State Highway 16, near Perkins; the large plants and pits just south of the American River between Citrus and Fair Oaks; and two large gravel plants outside of Tracy on the Corral Hollow road.

"Widespread exposures in the Coast Ranges of rock suitable for aggregate, together with gravel deposits of various sizes in the adjacent valleys, furnish an almost inexhaustible supply of stone for construction projects along San Francisco Bay. The greatest production comes from Alameda County where over 4,000,000 tons of aggregate are produced every year. Most of this is sand and gravel from the large pits around Pleasanton in the Livermore Valley.

Fig. 1. Pacific Coast Aggregates Company operation near Livermore, Alameda County. Rock, sand, and gravel are scraped from surface deposits by heavy earth-moving equipment, each unit carrying 20 tons. Material is gathered in a sub-surface hopper, fed onto a conveyor belt, and run through a washing, screening, and crushing plant. Sized material is then sent to stock piles via conveyor belts. Belt conveyors also connect the rail and truck-loading hoppers with the stock piles. In the background is the gravel pit and plant of Henry J. Kaiser Company. Pacific Coast Aggregates Company operation near Livermore, Alameda County
Fig. 2. An old photograph of the Healy-Tibbets rock quarry crushing plant and loading dock near Winehaven, west of Richmond, Contra Costa County. Crushed rock once was shipped by barge in large open boxes as shown in the left middle ground. Quarry was in sandstone of the Franciscan formation. Site is now occupied by installations connected with the Standard Oil company refinery at Richmond An old photograph of the Healy-Tibbets rock quarry crushing plant and loading dock near Winehaven, west of Richmond, Contra Costa County

"The earliest use of stone in the Coast Ranges was by the Indians. They quarried obsidian, soapstone, red ochre, and chert in Sonoma County and red ochre and schist in Contra Costa County.

"During the late eighteenth century and early nineteenth century, quarried stone and field stone were used in the construction of the missions and some ranch buildings. The principal building materials then used were wood and adobe, but stone entered into almost all of the structures to some extent. Commonly, stone was used in columns and foundations, and for trim.

"The earliest stone building in San Francisco was constructed in 1854; dressed granite from China was used. Soon after this, granite from Folsom came on the market. In the sixties quarries were opened, on Angel Island in San Francisco Bay to furnish a bluish sandstone, and near Petaluma in Sonoma County for the production of basalt. During the eighties and nineties light-brown sandstone was quarried at Benicia in Solano County, and near San Jose in Santa Clara County. Sandstone of other colors was marketed from quarries near Alameda, Livermore, and Hayward in Alameda County during the same period, and some stone was imported. The Old Mint at Fifth and Mission Streets in San Francisco was constructed in the eighties of sandstone from New Castle Island in British Columbia.

"Two of the most extensive and recent building programs using stone were at the University of California at Berkeley and Stanford University at Palo Alto. The University of California used gray granite from Raymond, Madera County. Stanford University used a local, light-brown sandstone from the Graystone quarries south of San Jose in Santa Clara County.

Fig. 3. Colusa sandstone quarry near Sites, Colusa County, from which building stone for such San Francisco structures as the Ferry Building, St. Francis Hotel, and Flood Building was taken. Sandstone beds of Upper Cretaceous age range from 18 inches to 35 feet in thickness. Colusa sandstone quarry near Sites, Colusa County

"As macadam roads and concrete construction became more common, large quarries for production of macadam and crushed stone were opened in the hills around San Francisco Bay. Locations such as Angel Island and Point San Pedro in Marin County and Point Richmond in Contra Costa County were especially favorable because of the availability of satisfactory stone and cheap water transportation. The rock at these localities is sandstone of the Franciscan formation. Basalt, limestone, chert, and sandstone from the Franciscan formation have been quarried intermittently at various other places on the San Francisco peninsula and in parts of Marin, Contra Costa, and Alameda Counties.

"The best gravel operations to be seen from the highway in this area are the large Kaiser and Pacific Coast Aggregates gravel pits and plants about a mile east of Pleasanton on the road to Livermore (circa 1950). Rock quarries and crushing plants can be seen about 1 miles south of San Rafael, and near Rockaway Beach on the coast highway in San Mateo County.

"Glass sand and foundry sand, often considered to be kinds of aggregate, have been produced at various time sin the vicinity of San Francisco Bay since 1920.

"Glass sand was processed for the market for some years from a belt of Eocene sandstone south of Pittsburg and Antioch. The sands were washed to remove clay, and the remaining high-silica sands was used for making glass. At present the washed sand is used only as foundry sand. Foundry sand with a natural clay bond is mined from the Eocene Tesla formation at the old Tesla coal mine in Corral Hollow. This operation represents what is probably the only underground mining of aggregate material in the bay counties.

"Foundry sand is also marketed from dune deposits in San Francisco and alluvial and marine sands in San Francisco County and northern San Mateo County."

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