Cross-section looking northwest at the North Arista, Three Sisters and Switchback vein systems with 2024 drill holes.
Plan view of Level 4 development with intersection of Sandy veins, Three Sisters vein system.
View of the Arista, Switchback and Three Sisters LOM stopes (blue) – looking northwest.
New Vein System With Higher Grades Adds to Future Potential
DENVER, April 04, 2025--(BUSINESS WIRE)--Gold Resource Corporation (NYSE American: GORO) (the "Company") is pleased to announce a summary of the 2024 exploration drill results at the Companies Don David Gold Mine ("DDGM") in Oaxaca, Mexico.
"We are excited to share the positive results of our 2024 exploration drilling program that indicate that the Three Sisters and Gloria vein systems will be significant contributors to our future resource at Don David," stated Allen Palmiere. "The discovery and definition of the system is exciting and is a testament to our team's dedication and expertise. These new vein systems have the potential to not only add to our resource potential but to also will enhance our bottom line with improved accessibility and reduced production costs. Underground development has recently intersected the system and the sample results thus far have confirmed the previous drill results. We remain committed to developing this system into the future mine plan and further advancing our exploration efforts with the goal of maximizing shareholder value and organic growth."
2024 EXPLORATION SUMMARY
The 2024 exploration drill program focused on underground infill and expansion drilling within the Three Sisters and Gloria vein systems as well as in veins of the North Arista system. Significant vein widths and grades identified through drilling have reinforced the emergence of the Three Sisters and Gloria systems as a major third vein system at DDGM, located between and north of the Arista and Switchback systems. The program yielded encouraging results, which were included in the updated S-K 1300 Technical Report Summary for DDGM released on March 5, 2025 (the "Report"), further demonstrating the potential of these vein systems.
The Company believes that the mine has significant potential to generate positive cash flow from the new areas of Three Sisters and Gloria, as well as other areas that have been discovered near the existing mining zones. These new vein systems offer easily accessible resources, situated close to the current mine portal and at significantly higher elevations than current production areas. The location of these vein systems should result in reduced haulage costs and reduced total production costs. In order to develop access and better define these new areas, an investment must be made in additional equipment and development.
2024 Drill Results: The exploration program included 23 underground infill and expansion drill holes, totaling 7,671 meters of diamond drilling at DDGM. Notable high-grade intersections were identified, advancing our exploration objectives by confirming the continuity and quality of polymetallic mineralization up-dip and along strike. The program confirmed and upgraded mineral resources from previous drilling campaigns within the Three Sisters and Gloria vein systems as well as in veins of the North Arista system. The Company expects to conduct additional exploration development in 2025 to enable further infill and expansion drilling to the northwest of the current defined vein extents in the Three Sisters/Gloria zone.
Below are select 2024 exploration infill drill results, including Gold Equivalent1 ("AuEq") and Net Smelter Return2 ("NSR") values from the Three Sisters and Gloria vein systems. All drill hole length composites are presented as Estimated True Widths3 ("ETW") in meters.
Hole No. 524001: Sandy 1 vein
6.85 m with 3.40 g/t AuEq and NSR value of $242/t
Includes: 2.07 m with 6.71 g/t AuEq and NSR value of $476/t
Hole No. 524005: Sandy 2 vein
4.70 m with 15.53 g/t AuEq and NSR value of $966/t
Includes: 2.01 m with 21.08 g/t AuEq and NSR value of $1,298/t
Hole No. 524005: Gloria vein
3.00 m with 7.67 g/t AuEq and NSR value of $535/t
Includes: 1.22 m with 16.47 g/t AuEq and NSR value of $1,142/t
Hole No. 524008: Gloria vein
12.30 m with 4.77 g/t AuEq and NSR value of $348/t
Includes: 3.71 m with 6.17 g/t AuEq and NSR value of $487/t
Hole No. 524011: Sandy 1 vein
8.03 m with 1.04 g/t AuEq and NSR value of $152/t
Includes: 4.58 m with 1.35 g/t AuEq and NSR value of $199/t
Hole No. 524011: Sandy 2 vein
3.89 m with 6.22 g/t AuEq and NSR value of $435/t
Includes: 3.13 m with 9.20 g/t AuEq and NSR value of $632/t
Hole No. 524015: Sadie 2 vein
6.00 m with 5.53 g/t AuEq and NSR value of $405/t
Includes: 3.14 m with 9.70 g/t AuEq and NSR value of $691/t
Hole No. 524027: Sadie 2 vein
4.48 m with 16.65 g/t AuEq and NSR value of $1,073/t
Includes: 1.01 m with 36.10 g/t AuEq and NSR value of $2,314/t
Hole No. 524031: Sandy 2 vein
8.72 m with 5.03 g/t AuEq and NSR value of $347/t
Includes: 1.39 m with 25.09 g/t AuEq and NSR value of $1,667/t
Hole No. 524042: Sadie 2 vein
5.33 m with 10.26 g/t AuEq and NSR value of $666/t
Includes: 1.98 m with 13.77 g/t AuEq and NSR value of $893/t
__________________________
1
Gold Equivalent ("AuEq") g/t is calculated using only gold and silver grades using an Au:Ag ratio of 89:11 and metal prices of y $2,760/oz gold and $31oz silver.
2
Net Smelter Return ("NSR") is a calculated value of the estimated net revenues per tonne less transportation and refining costs and other miscellaneous payables. The NSR values calculated utilize metal price estimates of $2,760/oz gold, $31/oz silver, $4.15/lb copper, $0.89/lb lead and $1.31/lb zinc.
3
Estimated True Width ("ETW") for reported vein intercepts are based on 3D models of the individual veins. Estimates are determined in cross-section by measuring the modelled vein thickness perpendicular to the vein margins and through the midpoint of the drill hole intercept. Differences between individual ETW’s and downhole interval lengths will vary between drill holes, depending on drill hole inclination, variations in vein strike and dip, and overall geometries of the different vein systems.
Three Sisters and Gloria Vein Systems
Initial drill intercepts into what is now referred to as the Three Sisters vein system were made in 2017 from underground drill stations in the Arista vein system while targeting northern extensions of veins in the Switchback system. Significant progress in defining this third vein system at DDGM occurred in 2022 and 2023, thanks to targeted underground exploration drilling guided by geologic re-interpretation. In 2024, the geologic model for the Three Sisters and Gloria vein systems was refined and improved using all available underground drill data in preparation for the 2024 year-end resource update.
The Three Sisters and Gloria vein systems remain open to the northwest, up-dip and at depth. Positive results to date have guided the direction of both infill and expansion (step-out) drill programs at DDGM.
Mine Development – Three Sisters
In December 2024, DDGM commenced drift development to access the Three Sisters vein system. The development on Level 4 has successfully intersected the Sandy 1 and Sandy 2 veins, revealing widths of up to 7.5 meters within a complex of colloform banded, hydrothermal breccia quartz veins. Detailed production channel sampling of these veins has confirmed high-grade results, with individual samples returning up to 44.23 AuEq and $2,780/t NSR4.
__________________________
4
Individual production channel sample of 0.8 m width. Assays by Corporacion Quimica Platinum S.A. de C.V., Guanajuato, Mexico, an independent laboratory accredited by the Mexican Accreditation Entity, A.C. (Entidad Mexicana de Acreditacion, A.C. (EMA)).
Life of Mine Plan
The 2024 year-end estimates of Mineral Reserves and Mineral Resources included in the report are the base of DDGM’s Life of Mine ("LOM") plan. Conceptual stopes were created using Deswik Stope Optimizer software, applying a $120/t NSR cut-off grade. These stopes were then integrated into mine designs and schedules within Deswik to obtain the updated LOM plan. All stopes were evaluated for economic viability, with non-viable stopes excluded from the plan.
As of year-end 2024, measured and indicated Mineral Resources have a conversion rate of 88% to the LOM plan while inferred Mineral Resources have a conversion rate of 74%, resulting in a total average conversion rate of 80% of estimated Mineral Reserves and Mineral Resources.
Compared to the 2023 LOM plan, the 2024 LOM plan reflects a 10% increase in estimated Mineral Resources, primarily driven by a 307% increase of Mineral Resources in the Three Sisters area. Conversely, the Arista and Switchback areas show a decrease in Mineral Resources due to depletion. Additionally, some of the observed increase can be attributed to higher metal prices used in the NSR calculations.
Total Resource in LOM
Category
YE 2024
Tonnes
Conversion Rate
%
Measured & Indicated
1,322,000
88
Inferred
1,838,000
74
TOTAL
3,160,000
80
Measured and Indicated Resource in LOM
Zone
YE 2023
Tonnes
YE 2024
Tonnes
Difference
Tonnes
%
Arista
505,356
421,770
(83,586)
-17
Switchback
500,260
218,770
(281,722)
-56
Three Sisters
57,890
526,152
468,262
809
TOTAL
1,063,506
1,166,460
102,954
10
Inferred Resource in LOM
Zone
YE 2023
Tonnes
YE 2024
Tonnes
Difference
Tonnes
%
Arista
297,180
414,054
116,874
39
Switchback
219,069
285,658
66,589
30
Three Sisters
234,014
662,749
428,735
183
TOTAL
750,263
1,362,461
612,198
82
All Resource in LOM
Zone
YE 2023
Tonnes
YE 2024
Tonnes
Difference
Tonnes
%
Arista
802,536
835,824
33,288
4
Switchback
719,329
504,196
(215,133)
-30
Three Sisters
291,904
1,188,901
896,997
307
TOTAL
1,813,769
2,528,921
715,152
39
NI43-101 Technical Report for Don David Gold Mine filed on SEDAR+
As per Canadian securities laws, the Company is pleased to announce that following the release of the Report, the Company has filed a corresponding National Instrument 43-101 Technical Report for DDGM (the "43-101 Report"). The qualified persons for purposes of the 43-101 Report are the same individuals named in the Company’s March 5, 2025 news release who prepared the S-K 1300 Technical Report. The 43-101 Report is available for review on SEDAR+ at www.sedar.com
Select 2024 Infill and Expansion Drill Results5 – Three Sisters, Goria and North Arista Vein Systems
HOLE
VEIN
FROM
TO
INTERVAL
ETW*
AU
AG
AuEq
CU
PB
ZN
NSR
ID
(m)
(m)
(m)
(m)
( g/t )
( g/t )
(g/t)
( % )
( % )
( % )
($/t)
524001
Sadie 2
291.55
294.22
2.67
2.63
1.47
60
2.14
0.06
0.18
0.43
130
Incl.
293.00
294.22
1.22
1.20
2.68
76
3.53
0.12
0.36
0.86
215
524001
Sandy 1
298.87
305.82
6.95
6.85
1.51
168
3.40
0.17
0.97
2.01
242
Incl.
303.72
305.82
2.10
2.07
2.41
383
6.71
0.38
1.69
3.39
476
524005
Sandy 2
338.57
343.54
4.97
4.70
14.13
125
15.53
0.32
2.83
7.13
966
Incl.
338.57
340.69
2.12
2.01
18.55
226
21.08
0.40
3.77
8.15
1,298
524005
Sasha 2
351.61
355.82
4.21
3.65
2.22
31
2.56
0.12
0.98
2.70
187
Incl.
352.79
355.12
2.33
2.02
3.32
35
3.71
0.15
1.30
3.85
267
524005
Gloria
365.78
369.70
3.92
3.00
0.86
607
7.67
0.38
1.09
2.42
535
Incl.
365.78
367.37
1.59
1.22
1.79
1309
16.47
0.72
2.30
5.06
1,142
524008
Sandy 2
287.44
295.48
8.04
3.35
1.85
155
3.59
0.03
0.09
0.23
213
Incl.
292.24
294.75
2.51
1.04
5.14
245
7.89
0.04
0.15
0.31
453
524008
Gloria
317.73
330.07
12.34
12.30
3.97
71
4.77
0.29
2.27
4.15
348
Incl.
322.47
326.19
3.72
3.71
5.16
90
6.17
0.25
5.09
6.85
487
524008
Splay Gloria
385.65
391.78
6.13
2.59
1.55
30
1.89
0.22
0.83
3.68
166
Incl.
387.63
389.40
1.77
0.75
3.44
36
3.84
0.24
0.59
2.76
257
524011
Sandy 1
335.62
346.10
10.48
8.03
0.60
40
1.04
0.17
2.35
4.93
152
Incl.
338.93
344.91
5.98
4.58
0.83
47
1.35
0.19
3.14
6.60
199
524011
Sandy 2
347.16
353.38
6.22
3.89
5.86
33
6.22
0.24
1.62
6.18
435
Incl.
349.44
353.38
3.94
3.13
8.72
42
9.20
0.32
2.36
8.51
632
524011
Sasha 2
357.83
361.67
3.84
3.24
1.67
32
2.02
0.16
1.34
3.47
174
Incl.
360.08
361.67
1.59
1.34
2.97
50
3.53
0.19
2.40
6.04
299
524015
Sadie 2
324.72
331.64
6.92
6.00
1.36
372
5.53
0.60
1.06
2.63
405
Incl.
325.88
329.50
3.62
3.14
2.10
677
9.70
0.87
1.54
3.73
691
524022
Sandy 1
241.28
245.85
4.57
2.94
0.73
257
3.61
0.15
0.44
1.05
245
Incl.
242.33
243.50
1.17
0.75
0.54
321
4.14
0.17
0.56
1.38
287
524022
Sandy 2
255.72
259.58
3.86
2.48
0.61
233
3.23
0.15
0.51
1.18
224
Incl.
258.61
259.58
0.97
0.62
1.28
362
5.34
0.13
0.74
1.78
360
524024
Gloria
248.86
254.31
5.45
3.86
1.48
39
1.92
0.44
2.64
9.89
272
Incl.
250.27
253.00
2.73
1.93
2.10
35
2.49
0.44
3.31
14.66
366
524027
Sadie FW
142.61
146.00
3.39
2.60
0.26
364
4.35
0.01
0.05
0.13
276
Incl.
145.41
146.00
0.59
0.45
0.21
769
8.84
0.01
0.15
0.27
564
524027
Sadie 2
261.99
267.16
5.17
4.48
2.08
1299
16.65
0.32
0.63
1.53
1,073
Incl.
266.00
267.16
1.16
1.01
3.01
2950
36.10
0.81
0.44
1.44
2,314
524027
Sandy 1
270.22
272.87
2.65
2.29
0.85
435
5.73
0.23
0.33
0.84
378
Incl.
271.15
272.25
1.10
0.95
1.34
793
10.24
0.45
0.64
1.69
681
524029
Sadie HW
217.00
219.75
2.75
2.25
0.61
310
4.09
0.04
0.09
0.25
259
Incl.
218.11
219.75
1.64
1.34
0.89
438
5.80
0.05
0.14
0.36
367
524029
Sadie 2
295.68
297.92
2.24
1.93
0.21
363
4.28
0.01
0.11
0.37
275
Incl.
297.10
297.92
0.82
0.71
0.56
963
11.36
0.03
0.29
0.92
730
524031
Sandy 2
302.92
315.17
12.25
8.72
1.69
298
5.03
0.24
0.96
2.08
347
Incl.
302.92
304.73
1.81
1.39
4.80
1809
25.09
0.55
3.32
5.53
1,667
524033
Splay Gloria
295.29
302.06
6.77
4.35
0.45
42
0.91
1.18
1.37
2.97
153
Incl.
297.90
300.16
2.26
1.45
0.26
50
0.82
1.70
1.81
3.21
178
524034
Splay Gloria FW
459.64
466.03
6.39
5.53
0.19
28
0.50
0.12
0.85
5.65
112
Incl.
459.64
461.76
2.12
1.83
0.47
37
0.88
0.23
1.63
7.44
168
524037
Sandy 1
334.70
336.93
2.23
1.83
1.07
288
4.29
0.05
0.08
0.12
266
Incl.
334.70
335.67
0.97
0.80
2.26
504
7.91
0.02
0.07
0.15
481
524037
Sandy 2
339.75
342.91
3.16
2.24
0.57
461
5.74
0.06
0.14
0.30
365
Incl.
340.96
342.91
1.95
1.38
0.89
733
9.12
0.06
0.19
0.40
578
524042
Sadie HW
296.60
300.42
3.82
2.93
1.30
127
2.72
0.03
0.08
0.14
163
Incl.
297.24
298.31
1.07
0.82
2.41
144
4.03
0.02
0.09
0.16
234
524042
Sadie 2
301.48
309.06
7.58
5.33
1.89
746
10.26
0.21
0.78
1.46
666
Incl.
306.25
309.06
2.81
1.98
1.98
1051
13.77
0.26
1.16
1.37
893
524046
Splay 31
253.08
258.40
5.32
2.66
1.54
116
2.84
0.30
11.33
12.69
456
Incl.
256.19
257.94
1.75
0.88
1.63
225
4.15
0.22
27.84
17.48
780
524048
Marena North
122.71
125.26
2.55
2.51
0.52
56
1.15
0.25
2.45
3.65
149
Incl.
124.31
125.26
0.95
0.94
1.29
133
2.78
0.30
6.36
9.16
356
524054
Marena North
118.02
120.94
2.92
2.24
0.43
38
0.86
0.21
2.34
2.83
119
Incl.
118.02
119.21
1.19
0.91
0.99
83
1.92
0.29
5.59
5.80
256
524055
Splay 31
248.06
252.00
3.94
3.02
0.27
52
0.86
0.10
0.78
11.68
203
Incl.
250.78
252.00
1.22
0.94
0.43
104
1.60
0.09
1.69
17.75
331
___________________________
5
Assays by ALS, Vancouver, BC Canada. The Company conducts a significant QA/QC program which includes the insertion of assay standards, blanks, and duplicates in the sample stream to ensure the assay lab results are within specified performance levels.
About GRC:
Gold Resource Corporation is a gold and silver producer, developer, and explorer with its operations centered on the Don David Gold Mine in Oaxaca, Mexico. Under the direction of an experienced board and senior leadership team, the Company’s focus is to unlock the significant upside potential of its existing infrastructure and large land position surrounding the mine in Oaxaca, Mexico and to develop the Back Forty Project in Michigan, USA. For more information, please visit the Company’s website, located at www.goldresourcecorp.com.
Forward-Looking Statements:
This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking words such as "plan," "target," "anticipate," "believe," "estimate," "intend" and "expect" and similar expressions are intended to identify such forward-looking statements. Such forward-looking statements include, without limitation, (i) the potential of the Three Sisters and Gloria vein systems and the Company’s expectation regarding its drilling and exploration activities in 2025. All forward-looking statements in this press release are based upon information available to the Company as of the date of this press release, and the Company assumes no obligation to update any such forward-looking statements. Forward-looking statements involve a number of risks and uncertainties, and there can be no assurance that such statements will prove to be accurate. The Company’s actual results could differ materially from those discussed in this press release. Forward-looking statements are subject to risks and uncertainties, including delays or challenges in satisfying the closing conditions of the offering. Additional risks related to the Company may be found in the periodic and current reports filed with the Securities and Exchange Commission by the Company, including the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, which are available on the SEC’s website at www.sec.gov.
