Mr. Steve Rogers reports
NAUTILUS MINERALS DEFINES 410 MILLION TONNE INFERRED MINERAL RESOURCE
Nautilus Minerals Inc.'s 100-per-cent-owned subsidiary, Tonga Offshore Mining Ltd. (TOML), has confirmed that Golder Associates Pty. Ltd. has completed a maiden mineral resource estimate for TOML's Clarion-Clipperton fracture zone (CCZ) polymetallic nodule project, located within the central Pacific Ocean.
The inferred mineral resource has been reported at a range of abundance cut-offs and is summarized in the associated table.
INFERRED MINERAL RESOURCE ESTIMATE FOR TOML AREAS A-D WITHIN THE CCZ
Abundance cut-off Abundance Ni Co Cu Mn Polymetallic nodules
(wet kg/m2) (wet kg/m2) (%) (%) (%) (%) (x 106 wet tonnes)
4 8.9 1.2 0.24 1.1 26.9 440
5 9.1 1.2 0.24 1.1 26.9 420
6 9.4 1.2 0.24 1.1 26.9 410
7 9.8 1.2 0.24 1.1 26.8 370
8 10.4 1.2 0.24 1.0 26.7 310
Resource estimates prepared by Matthew Nimmo, principal geologist, Golder
Associates, Queensland, Australia. Mr. Nimmo is a member of the Australian
Institute of Geoscientists, a full-time employee of Golder and fulfills the
requirements to be a qualified person for the purposes of National
Instrument 43-101.
The resource is classified as inferred. As the nodules effectively form a
single layer on the seafloor, abundance (kilograms/square metre) is used
rather than volume to define the mineral resource tonnage.
Nautilus president and chief executive officer Steve Rogers commented: "Our maiden mineral resource estimate for the CCZ again highlights the enormous potential of seafloor resources. We believe that the advance in processing and offshore technologies over the last 20 years now makes the extraction of these significant resources technically feasible."
The reduced social disturbance associated with deep-sea mineral production and the development of a strong regulatory framework by the International Seabed Authority since 1994 are key elements that set this project apart from large land-based resource developments.
Mr. Rogers added that: "At Nautilus Minerals we are hugely excited to be leading the development of this enormous, currently untapped potential on the seafloor. Our priority focus must remain with our high-grade Solwara 1 seafloor massive sulphide (SMS) project, and other prospective SMS systems in PNG and Tonga. With the immense polymetallic nodule mineral resources of the CCZ however, we have to start the engineering and evaluation processes now to realize this opportunity at the appropriate time in the future. There is the potential for a further update of this mineral resource estimate, in that approximately 30 per cent of our licence area is not included in the estimate, but both of these areas are known to have nodules present from limited sampling work carried out to date."
General background
The nodules occur within the CCZ of the tropical north Pacific in water depths generally between 4,000 and 6,000 metres. They contain significant grades of manganese, nickel, copper and cobalt, and form by the precipitation of metals on the seafloor, either directly from ocean waters, or via decomposing micro-organisms and/or their effluent in benthic sediments.
Basis of the mineral resource estimate
Golder has estimated the mineral resource for the TOML CCZ project using:
- Sample data collected by pioneer contractors (Deep Ocean Resources
Development Co. (DORD, of Japan), Association Francaise d'Etude et
de recherche des NODules oceaniques (AFERNOD, of France),
Yuzhmorgeologiya (state-owned company of the Russian Federation)), and
provided to TOML and Golder by the International Seabed Authority;
- Ordinary kriging for nickel, cobalt, copper and manganese grades;
- Inverse distance for nodule abundance and tonnage.
Samples used for the resource were collected by the pioneer contractors during various exploration cruises, using free-fall-sampling devices. The resulting samples were stored on the vessel, and then on arrival at port dried and crushed. Nickel, copper, iron and cobalt were normally assayed using atomic absorption, with manganese measured by photometric (electrometric) titration. The resulting sample locations and assay results were presented to the International Seabed Authority (ISA) as part of the process whereby the pioneer contractors hand over half of their prospect areas (of equal value) to the ISA for inclusion in the reserve area set aside for developing nations such as Tonga.
The data provided by the contractors are not supplied with any quality assurance or quality control, although some QA/QC is known to have been performed at the time (there was no requirement however to submit this to the ISA). TOML has accessed these data for the purpose of this mineral resource estimate. As part of the verification requirements, Golder also contacted pioneer contractors directly to provide confirmation of the data sets and methodologies used. Checks were also undertaken by comparison of the different data sets (those covering the TOML blocks) and by comparison of these data with the larger ISA data set covering the entire CCZ (see associated tables for raw sample statistics). These checks showed that:
- Only four of the total 2,212 data points provided were suspected of
being erroneous (and are likely data entry errors that occurred with the
one contractor).
- Box plots and log-probability plots comparing the various assay data and
distributions show the TOML abundance, Ni, Cu, Co and Mn data compare
well with the full ISA data set. Variations between the data sets are
attributed to both spatial variability, and minor differences in sampling
and assaying methods of the various contractors.
- Quantile-Quantile (QQ) plots show the TOML abundance, Ni, Cu, Co and Mn
data compare well with the total ISA database, but with divergence at
the tails of the distributions, while Co and nodule abundance tend to be
biased slightly lower for the TOML data.
Assay data for the four key elements (Ni, Cu, Co and Mn) are very consistent and widespread over large areas of the CCZ. The key variable for future resource classification is nodule abundance. Determining short-range variability for nodules will be required to increase resource classification to higher levels of indicated and measured.
The verification also involved review of the data by the independent qualified person, Dr. Charles Morgan. Dr. Morgan has considerable experience in the CCZ nodules, having been a scientist on board the Lockheed Martin consortia program in the 1980s and having been a consultant to the ISA in various capacities, including as a member of the legal and technical commission, and in the preparation of resource estimates for the ISA. Golder considers the sampling data are suitably supported and maintained by the ISA for use in the calculation of an inferred resource.
The estimate is current as of Sept. 18, 2012, and only incorporates blocks A to D of the TOML licence (approximately 70 per cent of the licence area). Blocks E and F are known to host nodules from limited sampling, and represent significant exploration upside to the mineral resource (see associated tables). Additional elements are reported to be present in CCZ nodules, with rare-earth elements being of particular note, and these provide additional potential for the project. All of the blocks are located at a depth of between 4,000 metres and 6,000 metres below sea level.
Other relevant information
The ISA is an autonomous international organization established under the United Nations Convention on the Law of the Sea (UNCLOS) and the 1994 implementation agreement. The ISA regulates the area beyond national jurisdiction under the terms of UNCLOS and the law of the sea. As of May 15, 2011, UNCLOS has been signed by 162 parties, mostly independent states and the European Union. The only notable absentee signatory is the United States. Part XI of UNCLOS, and its subsequent implementation agreement of 1994, deals with mining of minerals from the seafloor in the area.
The ISA has also developed regulations for prospecting and exploration for polymetallic nodules, seafloor massive sulphides and cobalt-rich crusts within the area. On Jan. 11, 2012, TOML signed a contract for exploration for polymetallic nodules with the ISA covering an area of approximately 75,000 square kilometres in six blocks within the CCZ. TOML is registered in Tonga, is subject to the laws of Tonga and is sponsored by Tonga under the law of the sea. The contract is for an initial term of 15 years.
The ISA, at its 18th session in Jamaica in 2012, started the process of developing regulations to cover the exploitation of nodules. Royalties and taxes payable on any future production from the property will only be finalized once the ISA has developed its exploitation code. The code will need to include the key principles of UNCLOS.
TOML has agreed to a royalty with the Tongan government as part of its sponsorship agreement of $1.25 (U.S.) per dry tonne for the first three million dry tonnes of nodules mined per year and 75 U.S. cents per dry tonne for all subsequent tonnes mined thereafter in that same year. Nautilus and TOML are parties to a contract with Nauru Ocean Resources Inc. (NORI) and NORI's current shareholders, pursuant to which Nautilus increased its indirect ownership interest in TOML from 50 per cent to 100 per cent in exchange for its 50-per-cent indirect interest in NORI. That contract provides, among other things, a value normalization process in respect of TOML and NORI's licences to explore polymetallic nodules in the area. The process is triggered by TOML and NORI achieving a resource pursuant to National Instrument 43-101. NORI has not yet disclosed a resource estimate in respect of its licences.
Recommendations
It is recommended that future work on the TOML licences aim to determine an inferred mineral resource estimate for areas E and F, and increase the resource classification for parts of the other areas to indicated or measured mineral resource. Additionally, key modifying factors will be constrained to a point where a mineral reserve may potentially be estimated. It is recommended that future work include:
Exploration phase
- Exploration surveys for detailed bathymetry;
- Sampling on TOML areas E and F to define inferred mineral resources for
these areas;
- Sampling at sufficient detail on the best of the defined inferred
mineral resources to define short-range variability, assay variance and
trends, density, and other critical data;
- Assaying of all samples collected for additional elements, including but
not limited to REE, potential contaminants and any other elements
that may aid economic studies;
- Widespread and detailed study of dry and wet density of the nodules on
the TOML licence, including study of free and crystallization water
contents;
- Side scan sonar survey of TOML licence areas where appropriate to image
nodule occurrence;
- Baseline environmental studies.
Study phase
- Engineering and metallurgical studies, and design work for both the
onshore and offshore components;
- Preliminary economic and commercial studies to provide scoping estimates
for capital expenditures and operating expenditures for mining, transportation and processing options.
Possible budgets required to complete the exploration phase over the next two years may total $2-million (U.S.) to $4-million (U.S.). Nautilus has sufficient funds to undertake this work or may choose to look for a partner.
SUMMARY OF HISTORIC GRAB SAMPLES AREA A
Mn Co Ni Cu Abundance
(%) (%) (%) (%) (wet kg/m2)
Count 18 18 18 18 18
Minimum 21.46 0.15 0.71 0.46 2.68
Maximum 30.05 0.30 1.47 1.51 17.93
Mean 25.40 0.22 1.14 1.00 10.12
Median 25.50 0.21 1.15 1.02 9.19
Standard deviation 2.44 0.04 0.24 0.35 5.08
Coefficient of variation 0.10 0.18 0.21 0.35 0.50
SUMMARY OF HISTORIC GRAB SAMPLES AREA B
Mn Co Ni Cu Abundance
(%) (%) (%) (%) (wet kg/m2)
Count 88 88 88 88 88
Minimum 10.30 0.02 0.53 0.40 0.03
Maximum 31.20 0.35 1.51 1.40 26.00
Mean 25.40 0.25 1.16 0.94 8.82
Median 26.55 0.25 1.23 1.02 8.09
Standard deviation 4.19 0.06 0.23 0.26 5.87
Coefficient of variation 0.16 0.22 0.20 0.27 0.67
SUMMARY OF HISTORIC GRAB SAMPLES AREA C
Mn Co Ni Cu Abundance
(%) (%) (%) (%) (wet kg/m2)
Count 78 78 78 78 78
Minimum 22.01 0.14 0.93 0.71 1.35
Maximum 30.90 0.32 1.42 1.44 21.25
Mean 27.91 0.25 1.27 1.15 9.98
Median 28.55 0.25 1.29 1.19 9.17
Standard deviation 2.13 0.03 0.10 0.15 4.20
Coefficient of variation 0.08 0.13 0.08 0.13 0.42
SUMMARY OF HISTORIC GRAB SAMPLES AREA D
Mn Co Ni Cu Abundance
(%) (%) (%) (%) (wet kg/m2)
Count 42 42 42 42 42
Minimum 22.79 0.19 1.09 0.79 0.12
Maximum 30.45 0.30 1.44 1.36 16.37
Mean 28.52 0.22 1.31 1.16 7.68
Median 28.76 0.22 1.32 1.17 7.78
Standard deviation 1.47 0.02 0.08 0.10 4.09
Coefficient of variation 0.05 0.10 0.06 0.08 0.53
HISTORIC GRAB SAMPLES AREA E
Water depth Mn Co Ni Cu Abundance
(m) (%) (%) (%) (%) (wet kg/m2)
4,542 26.83 0.16 1.11 1.14 18.18
4,497 24.04 0.21 1.01 0.88 6.73
4,851 25.64 0.18 1.21 1.04 9.24
4,577 27.5 0.16 1.29 1.13 9.2
HISTORIC GRAB SAMPLES AREA F
Water depth Mn Co Ni Cu Abundance
(m) (%) (%) (%) (%) (wet kg/m2)
4,073 32.4 0.17 1.33 1.31 9.3
4,073 32.4 0.16 1.27 1.29 13.7
HISTORIC SAMPLES FROM THE RESERVED AREAS OUTSIDE THE TOML LICENCES
Mn Co Ni Cu Abundance
(%) (%) (%) (%) (wet kg/m2)
Count 2,188 2,188 2,188 2,188 2,188
Minimum 4.14 0.05 0.15 0.12 0.01
Maximum 35.62 3.23 1.75 1.62 52.20
Mean 27.47 0.21 1.25 1.04 8.21
Median 28.47 0.21 1.30 1.09 7.10
Standard deviation 4.06 0.08 0.20 0.24 6.06
Coefficient of variation 0.15 0.40 0.16 0.24 0.74
Matthew Nimmo of Golder, independent qualified person, has prepared the technical information that forms the basis for this press release.
Pursuant National Instrument 43-101, Nautilus Minerals will file an independent technical report within 45 days in respect of this mineral resource estimate.
We seek Safe Harbor.
© 2025 Canjex Publishing Ltd. All rights reserved.