Midnight Sun Extends Dumbwa Copper Deposit to Over 5.3 Kilometres; Remains Open Along Strike With Drilling Ongoing
Midnight Sun Extends Dumbwa Copper Deposit to Over 5.3
Kilometres; Remains Open Along Strike With Drilling Ongoing
Results include: 93m @ 0.40% Cu, 80m @ 0.39% Cu, 44m @ 0.53% Cu,
and 36m @ 0.58% Cu
Vancouver, British Columbia, May 13 , 2026 – Midnight Sun Mining Corp. (TSXV:
MMA / OTC QX: MDNGF) (“Midnight Sun” or the “Company”) is pleased to report
results from drillholes completed on its wholly owned Dumbwa copper deposit,
located in Solwezi, Zambia. Dumbwa is in the southeast portion of the Company’s
Solwezi Project, centered in the heart of the prolific Domes Region - flanked to the
north by First Quantum’s Kansanshi mine and west by Barrick’s Lumwana mine.
Drilling has now surpassed 200 holes for a total of over 42,000 metres (“m”) and
results to date confirm near surface copper sulphide mineralisation, over a
continuous strike length of 5.3 kilometres (“km”) ( see Figures 2 and 3 ), with assays
received for the first ~4km of drilled strike. The initial discovery and delineation drill
program continues with 4 rigs focussed on growing the deposit to the north along
strike and to extend previously drilled mineralisation east and west. Quality control
issues related to laboratory analysis have been resolved, and the related backlog of
assays are now largely caught up (see below).
The Company plans to host a technical webinar with Midnight Sun ’s COO, Dr. Kevin
Bonel, to discuss the results announced in this news release. Details will be included
in a separate news release.
Top 20 Drill Highlights:
Hole ID From (m) To (m) Interval (m) Cu (%)
DBW-25-099R 58 60 2 0.54
152 245 93 0.40
29 33.78 4.78 0.31
DBW-25-123 59 67 8 0.44
127 207 80 0.39
DBW-25-036 0 44 44 0.53
and 119.54 137 17.46 0.37
DBW-25-111
52 57 5 1.75
63 79 16 0.35
132 221 89 0.25
DBW-25-122
11 20.6 9.6 0.18
77 91 14 0.19
106 142 36 0.58
including 127 142 15 1.03
171 238 67 0.30
DBW-25-147
0 17 17 0.20
41 102 61 0.34
including 41 47 6 1.30
82 85 3 1.38
111 126 15 0.27
154 168.05 14.05 0.51
182 183 1 1.34
DBW-25-064 0.7 47 46.3 0.42
DBW-25-114 26 32 6 0.21
43 87 44 0.37
122 208.5 86.5 0.15
DBW-25-149
23 40.84 17.84 0.85
Including 31 39 8 1.71
50.58 72 21.42 0.38
171 197.65 26.65 0.38
DBW-25-110
42 77 35 0.36
89 102 13 0.34
145 154 9 0.20
DBW-25-065 91 98 7 0.16
127 163 36 0.33
DBW-25-106
38 43 5 0.19
59 67 8 0.4
173 210 37 0.31
DBW-25-031
27 36 9 0.34
119 142 23 0.49
160 181 21 0.34
DBW-25-037 0 42 42 0.25
DBW-25-127
42 72 30 0.32
96 107 11 0.53
174.95 180 5.05 0.29
DBW-25-117
42 46 4 0.51
67 95 28 0.30
103 109 6 0.19
143 182 39 0.15
DBW-25-120
13 19 6 0.54
89 144.5 55.5 0.15
164 172 8 0.46
DBW-25-108 10 51 41 0.20
106 153 47 0.14
DBW-25-054
14 20 6 0.19
37 54 17 0.47
including 37 38 1 5.94
64.3 66 1.7 0.57
79 86 7 1.01
DBW-25-148
72.2 78 5.8 0.18
86 102 16 0.17
119 139.7 20.7 0.17
169 190 21 0.33
• Assay results based on four-acid digest, ICP-OES finish. Intervals listed are based on drilling intervals
and therefore are considered relative rather than true widths.
• The full table of assays including locations is available on the Company’s website and can be accessed
through this link: Dumbwa Drill Hole Location and Assay Table.
“What began as a geological concept has now been established as a significant
discovery, with over 5.3km of strike now tested and supported by more than 40,000m
of drilling. Our team is rapidly defining what is emerging as an exceptionally large,
near-surface, structurally controlled copper sulphide deposit” stated COO, Kevin
Bonel.
“We are developing a clear understanding of Dumbwa and can see the hallmark
‘pinch-and-swell’ geometry typical of major structurally controlled systems and have
confirmed unequivocally that Dumbwa is a basement-hosted, strain-related deposit,
geologically comparable in every way to Barrick’s Lumwana. We also recognize a
predictable grade distribution along strike, with broader higher- grade zones
separated by narrower lower- grade domains. Most importantly, we are continuing
to establish meaningful scale with each step north expanding the system and
mineralisation remaining open, alongside a clear plan to unlock additional
mineralisation within zones identified through earlier drilling.”
Figure 1: Dumbwa drilling to date, plotted on 11.2km Phase One copper-in-soil anomaly, target area.
Figure 2: Dumbwa drilling to date, magnified to show current 5.3km drilled strike extent, plotted on Phase One copper -in-
soil anomaly, target area.
Dumbwa Today – Geological Model Verified
The Company’s drilling has now surpassed 200 holes for a total of more than
42,000m over 5.3km of strike, and continues to confirm that Dumbwa is an
exceptionally large, very near surface, structurally controlled copper sulphide deposit
which remains open for growth. Drill testing has focussed on the upper ~220m of the
deposit with the intent of defining a resource amenable to rapid, low strip ratio, low-
cost future development. It is noted that some areas of similar mineralisation at the
nearby Lumwana pro ject can be traced to vertical depths well beyond 200m. At
Dumbwa, east-west width of the mineralised corridor ranges from 200m to greater
than 500m. Copper grades are variable ranging from thick lower grade intercepts (>
50 m @ <0.3%) to thick higher -grade intercepts (>25m@>0.5%). Grade variability is
pronounced along strike (north-south) and is influenced by cross-cutting northwest-
southeast structures that adversely affect the strain regime and subsequent
development of mineralised schists. In contrast, grades are relatively consistent east-
west within the higher, medium and lower grade zones, and across the width of the
mineralised corridor.
Figure 3: Assay grade shells superimposed on the Dumba soil anomaly showing the correlation between high soil anomalies
and medium to high grade mineralised intercepts at Dumbwa. Drilling continues to follow the soil anomaly north.