The Ariquemes project is one of the largest collections of highly prospective exploration leases in any tin region in the world.
The region has been one of the world’s major tin producers for some decades, but with most production coming from a range of privately owned mining operations, that were discovered by local prospectors, with little or no modern exploration having ever been undertaken.
A major government geological program in 2019 was the first attempt to bring modern techniques to the region, however the application of this work was then severely constrained by the Covid-19 pandemic in 2020. The project thus offer Orosur access to a major exploration opportunity.
Tenure
The Ariquemes project consists of package of 34 granted licences and applications in the Brazilian state of Rhondonia, totalling almost 2800km2.
The licences and applications are all held 100% by Brazilian company Meridian Mineracão Jabiru S.A, a wholly owned subsidiary of TSX.V listed Meridian Mining Ltd.
| LICENCE NAME | NO | STATUS | AREA(ha) |
| Alto Paraíso | 886204/2017 | Requerimento de Pesquisa / Exploration Application | 9708.06 |
| Itapuã D’Oeste | 886029/2017 | Requerimento de Pesquisa / Exploration Application | 8688.67 |
| Ariquemes | 886028/2017 | Requerimento de Pesquisa / Exploration Application | 7816.05 |
| Candeias Jamari | 886027/2017 | Autorização de Pesquisa Granted – second term renewal lodged | 9994.45 |
| PVH/Alto Paraíso | 886026/2017 | Autorização de Pesquisa Granted – second term renewal lodged | 9834.51 |
| Alto Paraíso/Candeias | 886025/2017 | Requerimento de Pesquisa / Exploration Application | 8175.86 |
| PVH/Alto Paraíso | 886024/2017 | Requerimento de Pesquisa / Exploration Application | 9709.67 |
| Alto Paraíso/Candeias | 886023/2017 | Autorização de Pesquisa Granted – second term renewal lodged | 9088.75 |
| PVH/Alto Paraíso | 886022/2017 | Autorização de Pesquisa Granted – second term renewal lodged | 9443.3 |
| PVH/Alto Paraíso | 886021/2017 | Autorização de Pesquisa Granted – second term renewal lodged | 8951.56 |
| Ariquemes/Alto Paraíso | 886256/2016 | Requerimento de Pesquisa / Exploration Application | 9993.04 |
| Ariquemes | 886255/2016 | Autorização de Pesquisa Granted | 5304.95 |
| Ariquemes | 886254/2016 | Autorização de Pesquisa Granted | 2334.23 |
| Machad. D’Oeste | 886249/2016 | Requerimento de Pesquisa / Exploration Application | 2833.03 |
| Machadinho D’Oeste | 886248/2016 | Autorização de Pesquisa Granted | 9206.26 |
| Ariquemes | 886245/2016 | Autorização de Pesquisa Granted | 9236.01 |
| Cujubim | 886244/2016 | Autorização de Pesquisa Granted | 440.56 |
| Candeias Jamari | 886098/2016 | Requerimento de Pesquisa / Exploration Application | 9942.04 |
| Alto Paraíso | 886097/2016 | Autorização de Pesquisa Granted – partial report submitted | 870.44 |
| Ariquemes | 886096/2016 | Requerimento de Pesquisa / Exploration Application | 9998.17 |
| Ariquemes | 886095/2016 | Requerimento de Pesquisa / Exploration Application | 9934.37 |
| Ariquemes | 886094/2016 | Requerimento de Pesquisa / Exploration Application | 9998.09 |
| Alto Paraíso/Candeias | 886093/2016 | Requerimento de Pesquisa / Exploration Application | 9917.03 |
| Ariquemes | 886092/2016 | Requerimento de Pesquisa / Exploration Application | 9971.42 |
| Alto Paraíso/Candeias | 886091/2016 | Autorização de Pesquisa Granted – partial report submitted | 9963.61 |
| Ariquemes/Alto Paraíso | 886090/2016 | Requerimento de Pesquisa / Exploration Application | 9817.08 |
| Ariquemes | 886089/2016 | Requerimento de Pesquisa / Exploration Application | 9964.79 |
| Ariquemes | 886088/2016 | Requerimento de Pesquisa / Exploration Application | 9963.59 |
| Alto Paraíso | 886079/2016 | Requerimento de Pesquisa / Exploration Application | 6739.44 |
| Alto Paraíso | 886078/2016 | Requerimento de Pesquisa / Exploration Application | 5362.86 |
| Alto Paraíso | 886077/2016 | Autorização de Pesquisa Granted – partial report submitted | 9921.17 |
| Alto Paraíso | 886076/2016 | Requerimento de Pesquisa / Exploration Application | 9951.84 |
| Ariquemes/Alto Paraíso | 886075/2016 | Requerimento de Pesquisa / Exploration Application | 9916.87 |
| Ariquemes/Rio Crespo | 886074/2016 | Autorização de Pesquisa Granted – second term renewal lodged | 3917.91 |
Joint Venture Details
A Joint Venture was signed with Meridian Mining on Jan 14th 2022.
The JV allows for Orosur to earn 75% equity in the project by investing US$3m in the project over a four-year period, in two phases:
- Phase 1- earn 51% interest by spending US$1m over a 24-month period
- Phase 2 – earn an additional 24% interest (for a total of 75%) by spending an additional US$2m over a subsequent 24-month period.
The JV will require the establishment of several Canadian and Brazilian companies which could take several months. The JV will not formally commence until this process is complete.
Geology
The Ariquemes Project is located within the “Rondoniano San Ignácio / Jamari Domain” The Domain formed through successive accretion of arcs, ocean basin closure and final oblique microcontinent–continent collision. Older basement rocks were affected by later collision-related deformation and metamorphism during the Sunsás Orogeny (1.25–1.00 Ga).
The tin mineralization event is particularly associated with the Neo-Proterozoic “Younger Granites” of Rondônia.
Exploration History
The Ariquemes tin district has produced approximately 3% of the world’s tin over the last 30 years.
Following the initial discovery of mineralization by a woodcutter clearing trees for a road, the region was soon home to thousands of artisanal miners . These early miners worked the alluvial and colluvial mineralization using an array of basic recovery techniques achieving modest recoveries (~50%). At its peak the region was producing more than 30,000 tonnes of tin per annum.
There is little or no foreign or public company involvement in these mines, with all being owned and operated by local companies or families. Modern exploration therefore has been limited.
Recent regional work in 2019 by the Brazilian geological survey (CPRM) has for the first time begun to explore the potential of the region with more up to date thinking and techniques and this work has formed the basis of increased interest in the region.
