76 



California Division of Mines and Geology 



Bull, 197 



as an impurity interspersed with calcite and as rela- 

 tively pure bands and zones that replace the limestone. 

 The purer types of dolomite are fine to coarse crystal- 

 line, off white to gray and cream colored. 



There have been no commercial developments of 

 carbonate rock for many years in the northern Santa 

 Lucia Range. Limestone at Bixby Creek and Limekiln 

 Creek (near Lucia) was burned for lime and exported 

 from Monterey County by ocean vessels prior to 1910. 

 Deposits at Tassajara Hot Springs, Lambert Ranch, 

 Limekiln Creek (near Chualar), and Jolon, however, 

 were developed only as small, local sources of lime 

 rock. 



Pico Blanco is the outstanding deposit in the region, 

 containing immense reserves of limestone of adequate 

 quality to meet the specifications of cement and other 

 limestone uses. Deposits at Bixby Mountain and 

 Limekiln Creek (near Lucia) probably contain sub- 

 stantial limestone reserves, but the limestone is of 

 variable quality and is distributed among numerous 

 small to medium-sized bodies. The Horse Canyon 

 deposit also may contain substantial reserves, but re- 

 quires closer examination before it can be evaluated. 

 Smaller reserves of limestone, and possibly dolomite, 

 are available at other deposits. Future development of 

 the various deposits is hindered by poor accessibility 

 and distance from transportation and market facili- 

 ties. Additionally, some interests would no doubt op- 

 pose any mining operation that might impair the 

 recreational and wilderness values of the region. 

 Nonetheless, development of the Pico Blanco lime- 

 stone and possibly other deposits undoubtedly will be 

 desirable in the future. 



The deposits are described alphabetically below. 



Bixby Creek deposit. Location: N'/j sec. 16 and S'/ 

 sec. 9, T. 18 S., R. 1. £., M.D., 16 miles south of Monte- 

 rey and 2 miles east of Bixby Landing; Point Sur 15- 

 minute quadrangle. Ownership: Not determined. 



This deposit was worked from 1904 to 1910 by Mon- 

 terey Lime Company of San Francisco (Logan, 1947, 

 p. 259). During this period, an estimated 75,000 tons 

 of limestone were produced and calcined in three 

 large vertical wood-fired kilns situated on Bixby 

 Creek (Aubury, 1906, p. 73). The lime was hauled by 

 overhead tramway to Bixby Landing on the coast 

 where it was loaded onto ships waiting off shore. 

 There were no roads into the area at the time of devel- 

 opment, although a dirt road now extends to the 

 deposit from the coast. 



Small detached masses of limestone centering near 

 N'X cor. sec. 16 extend northwestward over a distance 

 of half a mile and constitute the Bixby Creek deposit. 

 The masses of limestone are locally brecciated and cut 

 by numerous salients of granitic rock. The limestone 

 mainly is white and coarse crystalline and often con- 

 tains concentrations of graphite crystals. Analyses of 

 three samples of the better quality limestone from the 

 quarry area (Hart, 1966b, p. 62) are given below (in 



percent by weight): 



S.imp/e SuJ: Fe.O, A/.O, OO J/ffO Ko, 



LSL-5 .1.84% 0.10% 0.18% 51.82% 1.04% 0.02% 



LSL-6 1.82 0.08 a38 52.80 1.22 O.OJ 



LSL-7 1.96 0.12 0.30 52,93 1,06 0.03 



Development of the deposit consists of a series of 

 small quarries or pits situated near N'/ cor. sec. 16 

 about 1,000 feet north of the lime kilns. Future devel- 

 opment of the Bixby Creek deposit is limited by its 

 small size and remote location. 



Bixby Mountain deposits. Location: Mainly W'/j 

 sec. 14, sees. 15 and 23, and N'/^ sec. 25, T. 18 S., R. 1 

 E., M.D., 16 to 18 miles south of Monterey and 3 to 4 

 miles inland from the coast; Point Sur 15-minute 

 quadrangle. Ownership: Not determined. 



The Bixby Mountain deposits comprise a group of 

 carbonate bodies that extend southeastward for a dis- 

 tance of 3 miles from Bixby Creek near the north 

 border of sec. 15 to Little Sur River in N'/j sec. 25. 

 Situated in rugged, heavily vegetated terrain, the 

 deposits range in elevation from 800 feet at Bixby 

 Creek to 2,920 feet at Bixby Mountain. Trask ( 1926, p. 

 131, map) depicted the crystalline carbonate rocks as 

 northeast-dipping, elongated bodies lying at three or 

 four principal horizons within the Sur Series. The 

 largest body, located mostly in SW/, sec. 14, is indicat- 

 ed by Trask to cover an area 2,000 feet wide and more 

 than a mile long. Based on a partial, brief examination 

 of sec. 23 and 24 by Oliver E. Bowen (oral communi- 

 cation, 1961 and 1964), the carbonate bodies of Trask 

 are composite, consisting of smaller bodies of carbon- 

 ate rock associated with schist and other metamorphic 

 rocks of the Sur Series. Most of the deposits are mix- 

 tures of limestone and some dolomite and are com- 

 monly cut by fingers of granitic rock. The limestone 

 and dolomite are similar to other carbonate rocks in 

 the northern Santa Lucia Range, varying from white 

 to gray and from fine to very coarse crystalline. 

 Chemical analyses of typically white, medium- to 

 coarse-crystalline, good-quality limestone from the 

 main mass north of Bixby Mountain are given in per- 

 cent by weight by M. E. Maddock and C. C. Carlson 

 (1961, unpublished consulting report for O. P. Jen- 

 kins): 



It is possible that small to moderate-sized deposits of 

 limestone or dolomite of economic interest may exist 

 in the Bixby Mountain area, although insufficient 

 work has been done to delineate specific bodies. 

 However, preliminary examination does indicate no 

 large reserve at any one deposit. Future development 

 of the deposit will undoubtedly be hampered by the 

 remoteness and difficult access of the region. 



Other reference: Hart, 1966b, p. 62-63. 



