The type locality for the Hamburg Dolomite is at the Hamburg Mine along the southern branch of New York Canyon near Eureka, Nevada. Although originally described as a limestone (Hague, 1883), it was later corrected and amended to dolomite by Wheeler and Lemmon (1939).

The Hamburg Dolomite contains a trilobite fauna which is latest Middle Cambrian in age (Nolan and others, 1956).

In the Eureka area, the Hamburg consists of interbedded light and dark, massive, banded, and mottled grey limestones and dolomites, and local intraformational conglomerates. The upper Hamburg is commonly platy limestone while the lower portion of the formation contains thicker beds of mottled blue limestone which often contain chert stringers, and dark well-banded dolomites (Nolan and others, 1956). Much of the Hamburg is a gray, coarsely crystalline dolomite. Hydrothermal alteration in the Eureka area makes the unit porous and/or vuggy, and often the altered rock is highly brecciated containing jasperoid stringers. In the field the Hamburg is difficult to distinguish from the Eldorado Dolomite.

The Hamburg has also been mapped in the Cortez Mountains near Mount Tenabo (Merriam and Anderson, 1942) and in the Tuscarora Mountains 14 miles northwest of Carlin (Roberts and others, 1967). In the Cortez Mountains, the Hamburg is a light to dark gray, parallel bedded, sandy dolomite (Gilluly and Masursky, 1965). Sedimentary structures such as cross-lamination, slump structures, and mottling are abundant. Lighter beds contain fine-grained sand-size dolomite fragments, with darker layers containing coarser, angular to subrounded, dolomite fragments and blebs of organic material and pyrite. The darker layers have a fetid odor on fresh break. These dolomites are pervasively altered in the Cortez Mountains, with fine-grained dolomites locally contact metamorphosed to dolomitic marble and tactite (Gilluly and Masursky, 1965). The base of the Hamburg is not exposed and the top of the formation is an unconformity below the Eureka Quartzite (Stewart and McKee, 1977). In the Tuscarora Mountains, the Hamburg is a bluish-gray, coarsely crystalline, fractured dolomite. Thicknesses in both ranges are indeterminate (Roberts and others, 1967).

In the Ruby Mountains, lithologies temporally equivalent to the Hamburg have been mapped by Willden and Kistler (1979). These rocks are brown hornfels and phyllite which overlie rocks mapped as the Windfall Formation. In the southern Ruby Mountains, Millikan (1978) mapped the Hamburg as a basal unit of about 30 feet of platy, light gray, stylolitic, massive, trilobite-bearing limestone, overlain by about 530 feet of reddish-brown, thin-bedded argillaceous micrite, and an upper unit of about 380 feet of thin-bedded, greenish-brown, silty shale and mudstone which grade upward into the Dunderberg Shale (Millikin, 1978). To the south in the Buck Mountain-Bald Mountain area, the Hamburg is massive to thick-bedded, bleached limestone which has been metamorphosed to marble (Rigby, 1960).

In the Elk Mountains, Mathias (1959) correlated the lowest Cambrian sediments exposed with the Hamburg Dolomite. The Hamburg contains a lower portion of unfossiliferous, light-gray limestone in beds commonly 1 to 2 inches thick, and an upper unit of dense, dark-gray, siliceous limestone in beds 1 to 7 inches thick with minor thin gray chert beds (Mathias, 1959; Coats, 1985).

The Hamburg is 1,000 feet thick in the Eureka District, 1,200 feet in the Cortez Mountains (Gilluly and Masursky, 1965), 650 to 800 feet thick in the southern Ruby Mountains (Willden and Kistler, 1979), about 964 feet in the Sherman Mountain Quadrangle of the Ruby Mountains (Millikan, 1978), 90 feet in the Buck Mountain- Bald Mountain area (Rigby, 1960), and 320 feet in the Elk Mountains (Mathias, 1959).

The Hamburg is present in the Eureka Area, southern Ruby, Tuscarora, Cortez, and Elk Mountains.

The details of depositional setting are poorly understood for the Hamburg Dolomite. The oolitic, trilobite and intraformational conglomerate-bearing, locally cross-bedded sandy carbonates appear to represent shallow shelf sediments deposited in wave agitated waters.