New Pedrara Mexican Onyx Company Records, 1892-1937 (MSS 828)

Extent: .25 Linear feet (1 archives box, 1 map case folder)

Correspondence, reports, and maps of the New Pedrara Mexican Onyx Company, an American firm which mined onyx marble in Baja California, Mexico from 1893-1958.

The New Pedrara Onyx Company of New York and Chicago began prospecting for onyx marble in northern Baja California in 1892. Onyx marble, also known as banded calcite or Mexican onyx, is used in building construction and decorative arts. Company president Samuel Franklin Emmons (1841-1911) dispatched George Foster and William Denton (1828-1907) to survey mineral deposits in Baja California. After exploring the Punta Final region, they discovered the El Mármol site with rich deposits of onyx marble.

The New Pedrara Mexican Onyx Company was established in San Diego and began quarrying onyx marble at El Mármol in 1893. The slabs were shipped 50 miles overland on a wagon road to Puerto Santa Catarina, where they were barged to ships offshore for transport to San Diego. The onyx marble was cut and polished at the waterfront plant on 23rd Street; both raw and finished onyx were shipped to buyers worldwide. In 1910, the San Diego Union and Daily Bee described the New Pedrara Mexican Onyx Company as the "largest producers and shippers of onyx in the world." New Pedrara onyx marble was featured in the construction of the grand lobby of the Spreckels Theatre in San Diego in 1912.

The New Pedrara Mexican Onyx Company was incorporated in San Diego in 1906. In 1915, it was reorganized into the Lyman-Mills Onyx and Marble Company under Leslie B. Mills, and 1921 it became the Southwest Onyx and Marble Company. Demand for onyx marble declined during the 1930s and 1940s, and the quarry closed in 1958.

Records of the New Pedrara Mexican Onyx Company, an American firm which mined onyx marble in Baja California from 1893-1958. The collection includes correspondence, reports, maps, and ephemera regarding the establishment and operations of the company.

Container List


Box 1 Folder 1
Renouncement of Fortunata and Eureka silver mines by George Foster, 1892 January 19

Two signed documents embossed with the seal of Baja California Norte, in which Foster renounces his ownership of two silver mines in Baja California.

Box 1 Folder 2
Letters - Samuel Franklin Emmons, Washington, D.C., to George Foster, 1892-1893

Two letters from Emmons, president of the New Pedrara Onyx Company, authorizing George Foster to act as the company's agent in Baja California, and other business concerns. Mentions a shipment of onyx to the 1893 Chicago World's Fair.

Box 1 Folder 3
Letters - William Denton and George Foster, San Diego, with Matías Romero, Washington, D.C., 1893 October

Two letters from Denton and Foster describing challenges of geological prospecting (the terrain and legal troubles), and requesting help obtaining mineral rights in Baja California; and Romero's response.

Box 1 Folder 4
Reports by William Denton, 1893

Four reports by William Denton describing mineral deposits and mines near Punta Final, Baja California (including survey of San Francisco mine), and geological specimens from Cedros Island.

Oversize MC-024-07

Manuscript map on oilcloth of two Baja California mining properties. Solicitado por el Señor Santiago Bareño. 34.5 by 15.5 inches.

Oversize MC-024-07

Manuscript map on oilcloth depicting an area approximately between the 28th and 31st parallel. Red ink numbers along coasts likely record soundings. Place names noted: San Quintín, El Rosario, Ballenas Channel, Cedros Island (mislabeled Cerros Island), and a few others. Scale undetermined. 24 by 18.5 inches.

Box 1 Folder 5
Lower California Onyx Company investment brochure fragment, circa 1910
Box 1 Folder 6
Letters - Correspondence between Robert B. Moran, Nathan Moran, and Thomas H. Frothingham, 1925

Correspondence primarily between petroleum geologist Robert Breck Moran, Nathan Moran, and Thomas H. Frothingham ("Don Tomas") regarding banking, planning, and expenses for Baja California expeditions. Frothingham writes on American Consular Service letterhead from Guaymas, Mexico; other letters originate in San Diego, Los Angeles, and San Francisco. Other correspondents include a J. P. Brown and B. M. Elliott.

Box 1 Folder 7
Letter - Kathleen Loeser, San Francisco, to Robert Moran, 1937 October 27

Letter regarding Loeser family's mining documents.