Minco PLC Regulatory News (MIO)

BILBAO INFILL DRILLING RESULTS

Dublin, September 11, 2012, Minco plc (AIM - "MIO"), the Irish exploration and development company reports that Xtierra Inc. (TSXV | "XAG") today announced the results of a 2,032 metre 9-hole programme of infill drilling on the main Bilbao deposit. The objectives of the campaign were to check grade variability and to increase confidence in the resource blocks that would be mined within the first three to four years of underground production.

The drilling, which was centred in the previously drilled 50m grid, also permitted a refinement of the morphology of the main zone of mineralization which comprises the bulk of the deposit resource which currently stands at 10.62 million tonnes grading 2.00% lead, 2.13% zinc, 53.81 g/t silver and 0.19% copper in the indicated category. The drill-holes were designated Z1 to Z10, distinguishing them from previous holes which were designated X1 to X100. Results presented in the table below show very strong mineralization of excellent thickness has been intersected during the infill drilling programme. Hole Z4 intersected an almost continuous zone of mineralization at an average grade of 6.47% Pb+Zn together with 54g/t Ag over approximately 194m. Intersections of over 50m of resource grade or better mineralization were encountered in most drill holes which were equal to or better than anticipated.

The results of the infill drilling are now being incorporated into the geological model and a revised and updated independent resource estimate will be calculated for the feasibility study.

Conclusions

·; The recently completed infill drilling has confirmed the continuity of the main mineralization between the previous 50m spaced grid pattern in the core of the Bilbao resource on 25m spacing which may enable some of the resources to be upgraded from indicated to a measured category.

·; Intersection of the various mineralized horizons during the infill drilling program will enable a refinement of the precise morphology of the main mineralized zone thereby allowing a more accurate tonnage estimate of the resource.

·; Good to excellent base metal and silver grades have been substantiated in all of the verification drill-holes.

·; Drill hole Z10 encountered a small extension of the massive sulfide pod in the eastern part of the main mineralized zone although with lower lead-zinc-silver grades but with a stronger copper-gold signature (0.29g/t Au and 0.41% Cu over 6.0m).

·; There is good overall agreement with grades intersected in the infill drill-holes when compared with

those drilled earlier and which were used for calculation of the existing resource estimate. There appears to be a slight increase overall in zinc grades in the infill drill holes compared to earlier drilling.

Silver-Rich Zone

This infill-drilling is separate from the silver-rich breccia zone which was reported previously and which lies immediately to the south of the main Bilbao deposit. This zone extends over an area 350 x 100m in a north-south direction and appears to occupy a brecciated zone within the limestone sequence, the thickness of which is variable from about four to 20 metres. The resource estimate for Bilbao does not include these newly found silver rich veins and mantos (flat-lying replacement deposits) which are expected to eventually contribute to the silver resource at Bilbao.

*The planned drill-hole Z3 was not drilled and was substituted by hole Z10. Two drill-holes Z2 and Z8 were terminated prematurely before reaching the main ore body because of encountering water loss in cavernous fault zones.

Analytical Method

Core from each of the drill-holes was halved by diamond saw and samples taken for analysis usually at 1 metre intervals, or where a change in lithology occurred. These samples were submitted to the SGS laboratories in Durango for analysis by Inductively Coupled Plasma Optical Emission Spectrometer ICP-OES/14B by aqua regia digestion for 36 elements. Where analyses of the samples exceeded the upper detection limit for this method they were reanalyzed by ICP-AES/90Q which used a sodium peroxide fusion in order that high accuracy could be achieved and a precise grade (>5% precision) determined on ore grade material. For analysis of silver and gold, where initial grades exceeded 10g/t Ag, these were re-checked by Fire Assay (FAG323). Check analyses of 10% of the samples are being sent to the laboratories of ALS Minerals in Zacatecas.

Qualified Person

Mr. Terence N McKillen, B.A. (MOD), M.A., M.Sc., P.Geo, Chief Executive Officer, is the Qualified Person for the purposes of the AIM Guidance Note on Mining, Oil and Gas Companies dated March 2006. Mr. McKillen is a graduate in Natural Sciences (Geology) from Trinity College Dublin and holds a Master of Science degree in Mineral Exploration and Mining Geology from the University of Leicester. He has 40 years of exploration experience in Ireland and internationally.

About Minco

Minco plc, registered in the Republic of Ireland and listed on the AIM Market of the London Stock Exchange (AIM: MIO), is a mineral exploration and development company, currently engaged in lead-zinc and manganese development projects in Canada and in zinc-lead exploration in Ireland. Minco holds 30 million shares (approximately 29%) in Xtierra Inc. listed on the TSX Venture Exchange (TSX.V: XAG), advancing zinc‐silver projects in Mexico, and also holds 15 million shares (approximately 10%) in Buchans Minerals Corp. listed on the TSX Venture Exchange (TSX.V: BMC). Minco also holds a 2% NSR royalty on the Curraghinalt gold property in Northern Ireland currently being explored by Dalradian Resources Inc. (TSX: DNA).

About Xtierra Inc.

Xtierra Inc. is a Toronto based exploration and development company listed on the TSX Venture Exchange under the symbol "XAG". There are 103,272,142 shares issued and outstanding. The Company is completing a feasibility study on its Bilbao silver-zinc-lead-copper project in Zacatecas, Mexico. Xtierra's objective is to become a mid-tier producer of precious and base metals through the development of its Bilbao project as well as through exploration, organic growth and M & A opportunities.