Northern Copper Zone Internal Review Completed

Trading Symbol

AIM: AYM

28^th November 2022

Anglesey Mining plc

(“Anglesey” or “the Company”)

Northern Copper Zone Internal Review Completed

Anglesey Mining plc (AIM:AYM), the UK minerals development company, is pleased to provide the conclusions from an internal review of the Northern Copper Zone at Parys Mountain, one of the largest undeveloped copper deposits in the United Kingdom, and confirms the Northern Zone as an exciting opportunity.

 A PDF version of this announcement with added graphics can be viewed/downloaded from the Anglesey Mining website (www.angleseymining.co.uk)

or by pasting the following URL into any browser: https://www.angleseymining.co.uk/wp-content/uploads/2022/11/AYM_RNS_NCZ-28Nov2022.pdf

• The Northern Copper Zone (NCZ) at Parys Mountain has an Inferred resource estimate of 9.4Mt at 1.27% Cu, 0.38% Zn, 0.24% Pb, 5g/t Ag and 0.1g/t Au. This resource estimate was completed in 2012 by Micon International and is based on a Net Smelter Return cut-off of US$48/t.
• The NCZ was discovered in 1962. The deposit is interpreted as the downdip extension of the historical open pit mined at Parys Mountain and appears as a wedge-shaped block with the thin edge (15m wide) starting around 200m below surface that extends down to the thicker end (over 100m width) at a depth of around 525m below surface. It remains open both along strike to the east and at depth.
• Our review of historical drilling and documents shows an earlier internal resource estimate completed in July 1969 of 32.7Mt at 0.81% Cu (excluding other metals), which should not be considered compliant with any modern JORC or NI43-101 methodologies. Very few of the holes drilled before 1980 were assayed for gold but it was recognised that the NCZ contains gold with minor silver, zinc and lead.
• Preliminary metallurgical testwork completed in 1969 at Lakefield in Ontario demonstrated recoveries of up to 93.3% producing a copper concentrate grading 23.2% Cu
• The bulk of the mineralisation appears to be concentrated around 13 holes over a 400m strike extent. These holes range from 18m at 1.4% CuEq to 146m at 1.2% CuEq – the average intersection across these holes is 77m at 1.0% CuEq
• Subsequent drilling in 1973-75 targeted the up-dip ‘thin’ edge of the system meaning that down plunge and along strike areas of potential extensions are yet to be tested
• Work programmes over the next 12-months are planned to include drilling into the NCZ to confirm historical grades and continuity, increase confidence in the resource, collect samples for metallurgical testwork and conduct downhole geophysical surveying to try and identify further zones of high-grade mineralisation

Jo Battershill, Chief Executive of Anglesey Mining, commented: “Our internal review of the Northern Copper Zone confirms our belief that there remains substantial upside to the existing resource base and that future optimisations of the mine design could potentially lead to an extraction ratio greater than the projection  within in the 2021 Preliminary Economic Assessment of less than 50%.”

“Additional supporting documents show that historical metallurgical testwork demonstrated significantly better recoveries and concentrate grades than the Engine Zone testwork results used in the PEA. Recoveries of over 93% were achieved in the 1969 Northern Copper Zone testwork, which compares to the 80% expected for Engine Zone. While the PEA flowsheet was designed around a polymetallic deposit, the historical testwork suggests future optimisations could potentially lead to higher copper output from the Northern Copper Zone.”

“Under the PEA design, first mining from the Northern Copper Zone would commence towards the end of year 4, which provides sufficient time to infill drill the first production areas immediately adjacent to the decline as it is advanced into the White Rock & Engine Zones.”

“Therefore, we are looking to advance additional work programmes at the Northern Copper Zone over the course of the next 12-months. These programmes will include drilling to confirm the historical grades and continuity, lift the confidence to the Inferred resource, generate samples for metallurgical testwork and provide a platform for downhole geophysical surveying – with the aim of identifying additional zones of high-grade mineralisation. Ultimately, this information will feed into a resource update.

“We are currently working on the resource update for the White Rock and Engine Zone, which is expected to be complete over the next six weeks.”  

Northern Copper Zone – Mineral Resource Estimate

The 2012 mineral resource estimate for the Northern Copper Zone is provided below.

	Resource	Tonnes	Cu	Zn	Pb	Ag	Au
	Category	(Mt)	(%)	(%)	(%)	(g/t)	(g/t)
Northern Copper Zone	Inferred	9.38	1.27	0.38	0.24	5.0	0.1
	Total	9.38	1.27	0.38	0.24	5.0	0.1

The following assumptions were made for the 2012 Mineral Resource Estimate:

• Net Smelter Return cut-off value of US$48/t
• Price deck of US$2.50/lb Cu, US$1.25/lb Zn, US$1.00/lb Pb, US$17.50/oz Ag and US$1275/oz Au
• Costs of US$39.06/t for mining, processing and G&A
• Payability of 72%

Northern Copper Zone – Historical Significant Intersections

The following table outlines the significant broad intersections that have historically been drilled into the Northern Copper Zone.

Hole ID	Intersection  (m)	Grade  (% CuEq)1	From Depth (m)	Period Drilled
AMC19	13.6	2.4	313.4	2004 – 2008
A51	32.7	1.7	397.7	1981
Including	12.9	3.0	417.5
H30	80.9	1.5	297.6	1968 – 1970
Including	17.3	2.1	314.3
Including	15.5	4.6	377.0
A152	18.0	1.4	277.4	1973 – 1975
H342	146.3	1.2	349.9	1968 – 1970
Including	22.9	1.5	349.9
Including	21.3	2.3	430.7
H312	50.9	1.2	398.7	1968 – 1970
H31A2	63.0	1.0	392.6	1968 – 1970
Including	14.3	2.0	435.3
AMC16	45.5	1.0	283.5	2004 – 2008
H17A2	91.4	0.9	373.7	1968 – 1970
Including	16.8	1.5	443.8
M1C2	86.0	0.9	365.5	1962
H462	87.9	0.8	496.5	1968 – 1970
Including	30.8	1.0	515.4

¹ Equivalent grades based on pre-recovered grades and using following prices – Cu US$3.50/lb, Zn US$1.20/lb, Pb US$1.00/lb, Ag US$22.50/oz and Au US$1750/oz.

² Not assayed for gold

Competent Person

The information in this announcement which relates to an internal Anglesey review of the historical metallurgical testwork at the Northern Copper Zone has been approved by Mrs. Liz de Klerk, M.Sc., Pr.Sci.Nat., MIMMM who is a professional registered with the South African Council for Natural Scientific Professionals (SACNASP) and independent consultant to the Company. Mrs. de Klerk is the Senior Geologist & Managing Director of Micon International Co Limited and has over 20 continuous years of exploration and mining experience in a variety of mineral deposit styles. Mrs. de Klerk has sufficient experience which is relevant to the style of exploration, mineralisation and type of deposit under consideration and to the activity which she is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the "Australasian Code for reporting of Exploration Results, Exploration Targets, Mineral Resources and Ore Reserves" (JORC Code). Mrs. de Klerk consents to inclusion in the announcement of the matters based on this information in the form and context in which it appears.

About Anglesey Mining plc

Anglesey Mining is traded on the AIM market of the London Stock Exchange and currently has 280,675,721 ordinary shares on issue.

Anglesey is developing its 100% owned Parys Mountain Cu-Zn-Pb-Ag-Au deposit in North Wales, UK with a 2020 reported resource of 5.2 million tonnes at 4.3% combined base metals in the Indicated category and 11.7 million tonnes at 2.8% combined base metals in the Inferred category. 

Anglesey holds a 20% interest in the Grangesberg Iron project in Sweden, together with management rights and a right of first refusal to increase its interest to 70.2%.  Anglesey also holds 12% of Labrador Iron Mines Holdings Limited, which through its 52% owned subsidiaries, is engaged in the exploration and development of direct shipping iron ore deposits in Labrador and Quebec.

For further information, please contact:

Anglesey Mining plc

Jo Battershill, Chief Executive – Tel: [phone]

John Kearney, Chairman – Tel: [phone]

Davy

Nominated Adviser & Joint Corporate Broker

Brian Garrahy / Lauren O’Sullivan – Tel: [phone]

WH Ireland

Joint Corporate Broker

Katy Mitchell / Harry Ansell – Tel: [phone]

Canaccord Genuity Limited

Joint Corporate Broker

James Asensio / Harry Rees – Tel: [phone]

Scout Advisory Limited

Investor Relations Consultant

Sean Wade – Tel: [phone]

LEI: 213800X8BO8EK2B4HQ71