Company: CENX
Filing Date: 2025-03-03
Form Type: 10-K
Source: 0000949157-25-000024
Chunk: 63

Company: CENTURY ALUMINUM CO
Filing Date: 2025-03-03
Form: 10-K
Item: Item 2
Chunk 63
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 a mining joint venture in 1959 and beginning bauxite mining and exporting in 1963. The Company also built an alumina refinery in Clarendon that commenced operations in 1972 at an annual capacity of 0.5mdmt drawing on bauxites from the Mocho Mountain region upper Clarendon. Jamalco was formed in 1988 when the Government of Jamaica acquired a 50% interest in Alcoa’s mining and refining operations, with Alcoa remaining the managing partner. In December 2014, Alcoa sold its stake in Jamalco to the Noble Group. In May 2023 the Company purchased the interest from the Noble Group. General Alumina Jamaica Limited is the managing partner of the Jamalco joint venture.

Jamalco's bauxite consists of many deposits that occur as infilling within depressions on an eroded limestone surface. Referred to as a karst topography, these depressions result from the solution of the limestone over time. The shape of a typical deposit crudely resembles an inverted, flattened cone whose surface may cover many hectares.  Exploration for bauxite continues to be conducted on a regular basis to maintain sufficient mineral resources and reserves to meet refinery supply. 

At the start of mining, most identified deposits were on public land where the Company had ready access for drilling and mining within the constraints of restrictions imposed by the Mining Act. Currently, most of the remaining bauxite deposits are on private land parcels, which may have multiple owners. This situation of multiple ownership of deposits, typical of Jamaica, calls for a unique approach to detailed exploration, mine planning and bauxite extraction which has resulted in a lack of reportable mineral reserves. Specifically, Jamalco has a policy that once a consolidated land position is attained, then production in-fill drilling and mining is immediately initiated in order to minimize the outlay of capital. As such, it is Aluminpro’s opinion that the reserves are too small to merit reporting. This practice has been the basis for mine planning, extraction, blending and processing of bauxites in this area over the last 50 years and has supported a technically and 

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economically viable operation. Despite our operations, under subpart 1300 of Regulation S-K, we are considered an “exploration stage” company because we do not have mineral reserves to disclose.

The Jamalco facilities, including equipment, are in a maintained condition. Net book value of these facilities and equipment as of December 31,