RMM.L Regulatory News (RMM)

26 May 2021

Rambler Updates Mineral Resources for the Ming Copper-Gold Mine

London, England & Newfoundland and Labrador, Canada - Rambler Metals and Mining plc (AIM: RMM) ("Rambler" or "the Company"), a copper and gold producer, explorer and developer announces an update to copper, gold and silver contained in estimated Mineral Resources at the Ming Copper-Gold Mine, located in Eastern Canada.

A depleted Mineral Reserve is also reported. This Mineral Reserve is based on mining depletion from the previous estimate which had an effective date of 31 December 2019. Both the depleted resource and reserve estimates have effective dates of 31 March 2021.

BACKGROUND

· Throughout 2020, due to financial constraints, limited mining took place at Ming Mine, with respect to both production and development.

· Rambler limited all expenditures including diamond drilling in 2020. During this period, reconciliation of mined blocks, lithological modelling and resource targeting was carried out.

· Rambler has resumed underground diamond drilling, and plans to drill more than 15,000m in 2021. The drilling will be used to update the global resource model, with a planned update to the mining reserve to be delivered in 2022.

· As well as updating the global resource model, specific objectives in 2021 are to:

o In-fill drill for mine design and planning;

o Convert portions of the inferred resource to an indicated or measured confidence category; and

o Target prospective areas identified during the 2019 drilling campaign and 2020 model review.

RESOURCE SUMMARY

· The updated resource estimate includes 24.143 million tonnes of Measured and Indicated Resources grading 1.69% copper and 0.32 grammes per tonne ("g/t") gold, containing 900 million pounds (408,199 tonnes) of copper and 251 thousand ounces of gold at 1% copper cut-off. This represents a 6% increase in contained copper and 5% increase in contained gold relative to the previous resource estimate declared in 2017, after mining depletion.

· The Inferred Mineral Resources remain at 5.023 million tonnes grading 1.89% copper and 0.41 grammes per tonne gold containing 209 million pounds of copper and 66 thousand ounces of gold at 1% copper cut-off.

· All zones remain open for extension with further drilling, especially down dip from the current resource.

· Details of the new Mineral Resource estimate by zone appear in Appendix 1.

Table 1: Mineral Resource Summary for the Ming Copper-Gold Mine at 1% Copper Cut-off * (see note below)

The procedures used for the Mineral Resource estimation are consistent with the Canadian Institute of Mining and Metallurgy ('CIMM') (2014) best practices. See Mineral Resource note below for additional disclosures.

Dr Toby Bradbury, President and CEO, commented:

"It is encouraging to note that the overall high-grade copper Measured and Indicated resource endowment of the Ming Mine remains over 405,000 tonnes of copper, with an additional 95,000 tonnes of copper in the Inferred category.

"Our Mineral Reserve statistics, which will be updated in 2022 to incorporate the latest 2021 drill data, are themselves conservative, being based on USD$2.99 per pound copper, significantly less than current copper price.

"The diamond drilling program that resumed in Q1 2021 and continues is providing confirmatory data which supports the modelling of the resources. The in-fill drilling is being conducted in parallel with the redevelopment of the Ming Mine through 2021 and is a key element of risk mitigation for the future as we confirm our short and longer-term target areas for mining.

"All zones of mineralisation remain open at depth and we are pursuing well identified targets with a commitment to the proper development and exploration of the mine.

"The Ming Mine remains a world-class resource in a first-rate jurisdiction with potential to be further expanded. This mine, together with the Little Deer and Whalesback properties provide an exciting long-life mining platform for Rambler."

Lower Footwall Zone

The Lower Footwall Zone is the area currently being developed as the cornerstone source of future mined tonnes. This zone has potential to flex depending on the cut-off grade employed as shown in Table 2 below.

Table 2: Resource Cut-off Sensitivity Summary for the Lower Footwall Zone

Including the Massive Sulphide deposits, at a 1.5% copper cut-off, the entire measured and indicated mineral resource estimate consists of 11.581 million tonnes of material grading 2.21% copper and 0.49 grammes per tonne gold, containing 565 million pounds of copper and 181 thousand ounces of gold. This material will form the basis of a new NI43-101 compliant life of mine (LOM) plan for the Ming Mine that is planned for completion in 2022, building on the drill data from the 2021 program.

A comparison of the new Mineral Resource Estimate to the previously released Mineral Resource Estimate, effective date September 7, 2017, is shown in Table 3 below.

Table 3: Resource Summary at 1% copper cut-off (% change from September 2017 resource in brackets)

Mineral Reserve (Depleted)

The effective date of the mineral reserve estimate for the Ming Copper-Gold Mine is January 1, 2018 (reference press release dated 5 March 2018). Rambler intends to update the Mineral Reserve in 2022 to include the bulk of the diamond drilling and resource estimation program that is to be completed in 2021. Table 4 below provides a depletion of the reserves since January 1, 2018.

Table 4: Depleted Mineral Reserve Estimate Summary for the Ming Copper-Gold Mine** (see note below)

*Mineral Resource Notes

Mineral Resources are not Mineral Reserves and have not demonstrated economic viability. All figures are rounded to reflect the accuracy of the estimate. Cut‐off grades of 1.0 % copper for the massive sulphides, 1.25 grammes per tonne gold for any gold zones and 1.0 % copper for the stringer sulphides have been used in the estimate.

Cut‐offs are based on an NSR model and forecast long term metal prices of USD$2.99 per pound copper, USD$1,300 per ounce gold and USD$17.00 per ounce silver with a long-term USD/CDN FX rate of 1:0.80. Resources are inclusive of reserves.

**Mineral Reserve Notes

All figures are rounded to reflect the accuracy of the estimate; numbers may not total due to this rounding. This reserve statement reflects changes to reserves based on depletion due to mining over the 2018 to 2020 calendar years and through 31 March 2021. The NSR for the reserve material was calculated using an all-in cost of USD$72 per tonne of ore milled.

Long term metal prices used were USD$2.99 per pound copper, USD$1300 per ounce gold and USD$17.00 per ounce silver with a long-term USD/CDN FX rate of 1:0.80.

The procedures used for the Mineral Resource and Reserve estimations are consistent with the Canadian Institute of Mining and Metallurgy ('CIMM') (2014) best practices.

The effective date for the depleted Mineral Resource Estimate is March 31, 2021. The effective date for the depleted Mineral Reserve Estimate is March 31, 2021.

Mineral Resources and Reserves for the Ming Mine were estimated under the supervision of Mark Ross, P. Geo., who is a qualified person as defined by NI43-101.

Tim Sanford, P.Eng., is the Qualified Person responsible for the technical content of this release and has reviewed and approved it accordingly. Mr. Sanford is an employee of Rambler Metals and Mining Canada Limited. Tim Sanford consents to the inclusion in the announcement of the matters based on his information in the form and context in which it appears. Tim Sanford has sufficient experience, relevant to the style of mineralisation and type of deposit under consideration and to the activity that he is undertaking, to qualify as a "competent person" as defined by the AIM rules.

Tonnes referenced are dry metric tonnes unless otherwise indicated; unless otherwise noted all figures are quoted in $USD.

The information contained within this announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulations (EU) No. 596/2014 ('MAR') which has been incorporated into UK law by the European Union (Withdrawal) Act 2018. Upon the publication of this announcement via Regulatory Information Service ('RIS'), this inside is now considered to be in the public domain.

ABOUT RAMBLER METALS AND MINING

Rambler is a mining and development Company that in November 2012 brought its first mine into commercial production. The group has a 100 per cent ownership in the Ming Copper-Gold Mine, a fully operational base and precious metals processing facility and year-round bulk storage and shipping facility; all located on the Baie Verte peninsula, Newfoundland and Labrador, Canada.

Rambler's focus is to regain its production profile at 1,350 metric tonnes per day at 2% Cu in the course of 2021 and evaluate expansion opportunities from that base.

Along with the Ming Mine, Rambler also owns 100 per cent of the former producing Little Deer and Whales Back copper mines.

Rambler is listed in London under AIM:RMM.

For further information, please contact:

Website: www.ramblermines.com

Caution Regarding Forward Looking Statements:

Certain information included in this press release, including information relating to future financial or operating performance and other statements that express the expectations of management or estimates of future performance constitute "forward-looking statements". Such forward-looking statements include, without limitation, statements regarding copper, gold and silver forecasts, the financial strength of the Company, estimates regarding timing of future development and production and statements concerning possible expansion opportunities for the Company. Where the Company expresses or implies an expectation or belief as to future events or results, such expectation or belief are based on assumptions made in good faith and believed to have a reasonable basis. Such assumptions include, without limitation, the price of and anticipated costs of recovery of, copper concentrate, gold and silver, the presence of and continuity of such minerals at modeled grades and values, the capacities of various machinery and equipment, the availability of personnel, machinery and equipment at estimated prices, mineral recovery rates, and others. However, forward-looking statements are subject to risks, uncertainties and other factors, which could cause actual results to differ materially from future results expressed, projected or implied by such forward-looking statements. Such risks include, but are not limited to, interpretation and implications of drilling and geophysical results; estimates regarding timing of future capital expenditures and costs towards profitable commercial operations. Other factors that could cause actual results, developments or events to differ materially from those anticipated include, among others, increases/decreases in production; volatility in metals prices and demand; currency fluctuations; cash operating margins; cash operating cost per pound sold; costs per ton of ore; variances in ore grade or recovery rates from those assumed in mining plans; reserves and/or resources; the ability to successfully integrate acquired assets; operational risks inherent in mining or development activities and legislative factors relating to prices, taxes, royalties, land use, title and permits, importing and exporting of minerals and environmental protection. Accordingly, undue reliance should not be placed on forward-looking statements and the forward-looking statements contained in this press release are expressly qualified in their entirety by this cautionary statement. The forward-looking statements contained herein are made as at the date hereof and the Company does not undertake any obligation to update publicly or revise any such forward-looking statements or any forward-looking statements contained in any other documents whether as a result of new information, future events or otherwise, except as required under applicable security law.

APPENDIX 1

Table 1: Complete Mineral Resource Estimate, by zone, for the Ming Copper-Gold Mine - effective March 31, 2021 (Resources are inclusive of Reserves)

APPENDIX 2 - Glossary of Select Geological and Mining Terms

Term Definition

''Au'' gold

"Ag" silver

 ''concentrate'' in general, the saleable product resulting from crushing and grinding of mined ore in a processing plant along with concentration to remove impurities. Base metal operations can produce copper, lead and/or zinc concentrates

''Cu'' copper

''cut-off'' lowest grade of mineralised material considered economic, used in the calculation of ore reserves. Also used in reserve estimation, meaning all material higher than the given grade

''down plunge'' the direction within a rock mass indicated by linear features such as mineral lineation, fold axes or direction of maximum strain caused by deformation

''Footwall Zone'' or ''LFZ'' a mineralised zone beneath a geological feature such as a fault, another mineralised zone or bed

''grade'' relative quantity or the percentage of ore mineral or metal content in an ore body

''Indicated Mineral Resource'' that part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a reasonable level of confidence. It is based on exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes. The locations are too widely or inappropriately spaced to confirm geological and/or grade continuity but are spaced closely enough for continuity to be assumed ''massive sulphide'' occurrence of a concentrated mass of sulfide mineral such as pyrite, sphalerite or chalcopyrite in one place, as opposed to their being disseminated or occurring in vein

''measured mineral resource'' that part of a Mineral Resource for which quantity, grade or quality, densities, shape, and physical characteristics are so well established that they can be estimated with confidence sufficient to allow the appropriate application of technical and economic parameters, to support production planning and evaluation of the economic viability of the deposit. The estimate is based on detailed and reliable exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced

''Mineral resource'' a concentration or occurrence of material of intrinsic economic interest in or on the Earth's crust in such form that there are reasonable prospects for eventual economic extraction. Mineral resources are sub-divided, in order of increasing confidence, into Inferred, Indicated and Measured categories

''mineralised'' containing or impregnated with minerals

''National Instrument 43-101'' provides standards of disclosure for mineral projects in Canada. It is a legal requirement in Canada for all oral and written disclosure of scientific or technical information on mineral deposits

 ''ore'' rock that can be mined and processed at a profit

 ''oz'' troy ounce (=31.103 grammes)

''Probable mineral reserves'' measured and/or indicated mineral resources which are not yet proven, but where technical economic studies show that extraction is justifiable at the time of the determination and under specific economic conditions

''Proved mineral reserves'' measured mineral resources, where technical economic studies show that extraction is justifiable at the time of the determination and under specific economic conditions

''reserve'' that part of a resource that can be mined at a profit under reasonably expected economic conditions

''resource'' mineralised body for which there is sufficient sampling information and geological understanding to outline a deposit of potential economic merit

 ''stringer'' a thin, discontinuous mineral vein or rock layer

''sulphide'' a mineral containing sulphur in its non-oxidised form

''t'' a metric tonne