April 28, 2021

IMBO project

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Overview – Within Imbo, the Adumbi deposit's moving towards Tier 1 status

The Company acquired control of the Imbo project, as well as a number of other gold exploitation concessions, in the east of the Ngayu greenstone belt in the DRC in September 2019. The Company initially obtained a 71.25% interest in these projects, which subsequently increased to 84.68% in September 2020. The Imbo project contains numerous targets of significant growing interest including the three resource bearing deposits of Adumbi, Kitenge and Manzako, the deposits occurring within a 5-kilometre radius of each other.

Loncor is drilling a +/- 7,000 metre program at its flagship high-grade deposit Adumbi with the aim of confirming the additional significant gold resources (both within the US$1500/oz proposed pit outline and underground) to the Imbo Project’s current 3.466 million ounces of gold, with the deposit still open below +/- 650 metres below surface.

Details on the progress of the drilling at Adumbi can be seen below under the section - Exploration Upside Around Imbo.

Historically the Imbo area was mined on a relatively small scale in the 1930s by Belgian operators, with the majority of output originating from our main target, Adumbi.

Figure 1: Location of Imbo Project Area in Ngayu Belt

Imbo Project Area in Ngayu Belt [map]

Photo 1 - The Adumbi deposit forms a clear ridge on the topography

Adumbi deposit ridge [photo]

After assessing exploration results undertaken between 2014 to 2018, including re-logging of all previous boreholes and undertaking additional drilling at depth, Loncor announced on April 17 2020 the gold content of the inferred resource of the three deposits (Adumbi, Manzako and Kitenge) had increased by 49% to 2.503 million ounces (30.65 million tonnes @ 2.54 g/t Au), compared to the previous resource determination undertaken in 2014. Loncor has an attributable interest of 84.68% in this resource. On June 10 2020, a NI 43-101 technical report on the Imbo Project was filed on SEDAR and confirmed the inferred resource increase at the Imbo Project, having been prepared by Minecon Resources and Services Limited with an effective date of April 17 2020. A copy of the said report can be obtained from SEDAR at www.sedar.com.

On April 27 2021, Loncor announced a 44% increase in mineral resources at its Adumbi deposit in the Imbo Project (Loncor 84.68%). Compared to the inferred mineral resource of 2.19 million ounces of gold (28.97 million tonnes grading 2.35 g/t Au) outlined in April 2020 the inclusion of six holes from the 7000 metre 2020/21 program increased the Adumbi inferred mineral resource to 3.153 million ounces of gold (41.32 million tonnes grading 2.37 g/t Au), constrained within a US$1,500 open pit shell. 84.68% of this Inferred mineral resource is attributable to Loncor via its 84.68% interest in the Imbo Project (see Figure 2). On June 11 2021, a NI 43-101 technical report on the Imbo Project was filed on SEDAR and confirmed the inferred resource increase to 3.153 million ounces at Adumbi within the Imbo Project, having been prepared by Minecon Resources and Services Limited with an effective date of April 27 2021. A copy of the said report can be obtained from SEDAR at www.sedar.com. Further detail on the resource upgrade can be found on the resources page.

Table 1 below summarises the current Adumbi inferred mineral resource based on in-situ block cut-off at a 0.69 g/t Au for Oxide and Transition materials and 0.73 g/t Au for Fresh material and constrained within a US$1,500 per ounce optimized pit shell.

Table 1: Adumbi Deposit Inferred Mineral Resource by material type (with an effective date of April 27 2021)

Material TypeTonnage (Tonnes)Grade (g/t Au)Contained Gold Ounces
Oxide 4,623,000 2.24 333,000
Transition 3,674,000 2.53 299,000
Fresh 33,019,000 2.38 2,521 ,000
Total 41,316,000 2.37 3,153 ,000

Drilling continues to assess the underground potential at Adumbi. Loncor believes that during 2021 Adumbi could delineate a significant underground resource.

Recent drilling has suggested that the ore body at Adumbi may have a shallower plunge than previously predicted, a potential positive for resource ounce generation if it proves to be the case.

Figure 2: Adumbi Deposit Longitudinal Section Looking Northeast with Drill Hole Grade (g/t) x True Thickness (Metre) Product Contours

Cross section of Adumbi showing revised predicted plunge of deposit [map]

Figure 3: Geological Interpretation Surface Plan of the Adumbi Deposit

Geological Interpretation Surface Plan of the Adumbi Deposit [map]

Figure 4: Geological Cross Section A-B

Geological Interpretation Surface Plan of the Adumbi Deposit [map]

Figure 5: Geological Cross Section C-D Highlighting Improved Grades of LADD0017 Infill Hole

Geological Interpretation Surface Plan of the Adumbi Deposit [map]

Given the current Adumbi resource grades and likely pit size, Loncor believes the PEA may offer costs and economic margins similar to Kibali. If so, the PEA which started in Q2 2021 could hold significant potential value for shareholders.

Southeast of Adumbi there is ongoing exploration at Imbo East including gridding, soil sampling, trenching and channel sampling in order to generate potential drill targets (further detail can be seen within the Imbo East section of the website). The addition of exploration targets in relative close proximity to Adumbi creates the potential of a larger mining district, with all the upside that such a development would offer.

Figure 6: Deposits and emerging areas of interest within the Imbo Project Area

Imbo Project Area [map]

Summary of Ongoing Adumbi Drill Results

On November 30 2020, Loncor announced that the first core hole of its 7,000-metre drilling program at its Adumbi deposit intersected multiple gold sections including 20.33 metres grading 2.47 g/t gold (including 4.8 metres grading 5.40 g/t Au), 7.33 metres grading 5.80 g/t Au and 20.77 metres grading 1.72 g/t Au.

Mineralized sections are summarised in the table below:
Borehole NumberFrom (m)To (m)Intersected Width (m)Grade (g/t) Au
LADD001 202.58 223.35 20.77 1.72
LADD001 231.27 237.17 5.90 1.89
LADD001 251.27 258.60 7.33 5.80
LADD001 295.25 298.70 3.45 2.10
LADD001 301.62 321.95 20.33 2.47
LADD001 Incl. 317.11 321.95 4.80 5.40

Borehole LADD001 had an inclination of minus 65 degrees and azimuth of 220 degrees at the start of the hole and regular measurements of inclination and azimuth were taken at 30-metre intervals down the hole. All core was orientated and it is estimated that the true widths of the mineralized sections are 82% of the intersected width. All intercepted grades are uncut.

On December 22 2020, Loncor announced that the second core hole of its 7,000-metre drilling program at its Adumbi deposit intersected significant gold intersections of 33.30 metres grading 3.25 g/t gold (including 5.70 metres grading 7.00 g/t Au and 9.07 metres grading 5.11 g/t Au) and 10.45 metres grading 3.88 g/t Au.

Mineralized sections are summarised in the table below:
Borehole NumberFrom (m)To (m)Intersected Width (m)Grade (g/t) Au
LADD003 224.55 235.00 10.45 3.88
LADD003 253.50 286.80 33.30 3.25
LADD003 Incl. 253.50 259.20 5.70 7.00
LADD003 Incl. 277.73 286.80 9.07 5.11

Borehole LADD003 had an inclination of minus 57 degrees and azimuth of 220 degrees at the start of the hole and regular measurements of inclination and azimuth were taken at 30-metre intervals down the hole. All core was orientated and it is estimated that the true widths of the mineralized sections are 80% of the intersected width. All intercepted grades are uncut. Borehole LADD003 was drilled in place of LADD002 which was stopped after deviating from its intended target depth.

On January 5 2021, Loncor announced that the third core hole of its 7,000-metre drilling program at its Adumbi deposit intersected significant gold intersections of 28.00 metres grading 3.26 g/t gold (including 4.90 metres grading 6.96 g/t Au and 3.53 metres grading 8.30 g/t Au) and 20.30 metres grading 2.83 g/t Au (including 6.55 metres grading 4.64 g/t Au and 2.30 metres grading 7.25 g/t Au).

Mineralized sections are summarised in the table below:
Borehole NumberFrom (m)To (m)Intersected Width (m)Grade (g/t) Au
LADD004 429.00 457.00 28.00 3.26
LADD004 Incl. 432.00 436.90 4.90 6.96
LADD004 Incl. 450.62 454.15 3.53 8.30
LADD004 473.80 478.40 4.60 2.07
LADD004 505.85 526.15 20.30 2.83
LADD004 Incl. 506.85 513.40 6.55 4.64
LADD004 Incl. 523.85 526.15 2.30 7.25

Borehole LADD004 had an inclination of minus 70 degrees and azimuth of 220 degrees at the start of the hole and regular measurements of inclination and azimuth were taken at 30-metre intervals down the hole. All core was orientated and it is estimated that the true widths of the mineralized sections are 81% of the intersected width. All intercepted grades are uncut. LADD004 intersected the mineralized zone at a shallower depth than planned due to the upward deflection of the borehole.

On March 4 2021, Loncor announced further significant assay results from its Adumbi drilling program. The final infill core hole within the Adumbi open pit shell, LADD008 intersected 43.10 metres grading 1.68 g/t gold, 0.78 metres grading 21.8 g/t gold and 14.98 metres grading 3.62 g/t gold including 3.09 metres grading 13.28 g/t gold.

Mineralized sections for borehole LADD008 are summarised in the table below:
Borehole NumberFrom (m)To (m)Intersected Width (m)Grade (g/t) Au
LADD008 235.05 278.15 43.10 1.68
LADD008 291.80 298.90 7.10 1.34
LADD008 305.15 305.93 0.78 21.8
LADD008 323.80 338.78 14.98 3.62
LADD008 335.75 338.78 3.09 13.28

Borehole LADD008 intersected the mineralization at a vertical depth of 272 metres below surface and within the southeastern boundary of the US$1,500 open pit shell, and had an inclination of minus 65 degrees and azimuth of 218 degrees at the start of hole and regular measurements of inclination and azimuth were taken at 30-metre intervals down the hole. All core was orientated, and it is estimated that the true widths of the mineralized sections are 62% of the intersected width. All intercepted grades are uncut.

On March 25 2021, Loncor announced further significant assay results from its Adumbi drilling program. The deepest borehole drilled to date at its flagship Adumbi deposit, LADD009 intersected 32.15 metres grading 6.17 grammes per tonne (g/t) gold (including 1.46 metres grading 94.77 g/t Au), 15.36 metres grading 3.73 g/t gold (including 5.89 metres grading 6.56 g/t Au), 5.00 metres grading 3.17 g/t gold and 7.45 metres grading 1.48 g/t gold.

Mineralized sections for borehole LADD009 are summarised in the table below:
Borehole NumberFrom (m)To (m)Intersected Width (m)Grade (g/t) Au
LADD009 559.76 564.76 5.00 3.17
LADD009 581.90 614.05 32.15 6.17
LADD009 including 599.05 600.51 1.46 94.77
LADD009 629.56 644.92 15.36 3.73
LADD009 including 632.00 637.89 5.89 6.56
LADD009 650.50 657.95 7.45 1.48

Borehole LADD009 had an inclination of minus 75 degrees and azimuth of 218 degrees at the start of the hole and regular measurements of inclination and azimuth were taken at 30-metre intervals down the hole. All core was orientated, and it is estimated that the true widths of the mineralized sections are approximately 82% of the intersected width. All intercepted grades are uncut with maximum internal dilution equal to or less than 4 metres of intersected width. Borehole LADD009 intersected the mineralization at a depth of approximately 140 metres below the open pit shell.

May 25, 2021 – Latest Hole Drilled at Loncor’s Adumbi Deposit Intersects Significant Widths and Grades in Multiple Gold Zones.

Loncor announced further significant assay results from its drilling program within its 84.68%-owned Adumbi deposit at Imbo. Borehole LADD013 intersected 20.00 metres grading 4.21 grammes per tonne (g/t) gold (including 11.00 metres grading 6.91 g/t Au), 17.30 metres grading 2.48 g/t gold (including 8.20 metres grading 4.71 g/t Au) and 7.04 metres grading 2.68 g/t gold.

Mineralized sections for borehole LADD013 are summarised in the table below:
Borehole NumberFrom (m)To (m)Intersected Width (m)Grade (g/t) Au
LADD013 394.06 401.10 7.04 2.68
LADD013 418.65 438.65 20.00 4.21
LADD013 including 419.75 430.75 11.0 6.91
LADD013 452.30 469.60 17.30 2.48
LADD013 including 457.35 465.55 8.20 4.71

Borehole LADD013 had an inclination of minus 72 degrees and azimuth of 218 degrees at the start of hole and regular measurements of inclination and azimuth were taken at 30 metre intervals down the hole. All core was orientated, and it is estimated that the true widths of the mineralised sections are approximately 85% of the intersected width. All intercepted grades are uncut with maximum internal dilution equal to or less than 4 metres of intersected width. Borehole LADD013 intersected the mineralization at a depth of approximately 65 metres below the open pit shell.

These results suggest a shallower northwest plunge to the mineralization than the previously indicated sub vertical plunge at depth.

July 12, 2021 – Borehole LADD017 drilled at Loncor’s flagship Adumbi deposit, intersected 25.77 metres grading 6.24 grammes per tonne (g/t) gold (including 9.29 metres grading 9.68 g/t Au and 5.50 metres grading 9.75 g/t gold) while borehole LADD012 intersected 13.45 metres grading 3.63 g/t gold and borehole LADD014 intersected 11.80 metres grading 2.97 g/t gold (see Figures 2, 3, 4 and 5 above).

Mineralized sections for boreholes LADD012, LADD014 and LADD017 are summarised in the table below:
Borehole NumberFrom (m)To (m)Intersected Width (m)Grade (g/t) Au
LADD012 784.35 797.80 13.45 3.63
LADD012 including 784.35 786.35 2.00 9.56
LADD012 806.30 810.35 4.05 4.73
LADD014 670.00 681.80 11.80 2.97
LADD014 including 670.00 673.53 3.53 6.44
LADD017 45.55 62.70 17.15 1.90
LADD017 92.68 118.45 25.77 6.24
LADD017 including 100.76 110.05 9.29 9.68
LADD017 including 112.95 118.45 5.50 9.75

Note: It is estimated that the true widths of the mineralised sections for core holes LADD012, LADD014 and LADD017 are, respectively, 86%, 78% and 71% of the intersected widths in the above table.

August 20, 2021 – Loncor drilled the deepest hole so far in the program, LADD016 and it intersected 25.59 metres grading 2.39 grammes per tonne (g/t) gold (including 6.09 metres grading 4.78 g/t Au) and 8.09 metres grading 1.90 g/t Au.

In order to verify the potential at depth further holes will be drilled to similar depths with the aim of creating significant underground resources to add to the surface resources already in place at Adumbi.

Mineralized sections for borehole LADD016 are summarised in the table below:

Borehole NumberFrom (m)To (m)Intersected
Width (m)
Grade (g/t) Au
LADD016 672.85 680.94 8.09 1.90
LADD016 731.51 757.10 25.59 2.39
including 737.18 743.27 6.09 4.78
including 749.67 752.56 2.89 4.98
LADD016 765.55 768.36 2.81 2.42

Borehole LADD016 had an inclination of minus 75 degrees and azimuth of 218 degrees at the start of hole and regular measurements of inclination and azimuth were taken at 30 metre intervals down the hole. All core was orientated, and it is estimated that the true widths of the mineralised sections are approximately 71% of the intersected width.

Figure 7: Adumbi Longitudinal Section Looking Northeast with Drill Hole (Grade x Metre)

Figure 7: Adumbi Longitudinal Section Looking Northeast with Drill Hole (Grade x Metre) [map]

September 14, 2021 Results for infill drilling within the pit shell include borehole LADD018, 019, 021 and LADD022. Highlights included LADD021 which intersected 15.73 metres grading 5.28 grammes per tonne (g/t) gold (including 5.00 metres grading 13.70 g/t Au ) while borehole LADD018 intersected 25.72 metres grading 2.26 g/t gold and borehole LADD022 intersected 21.50 metres grading 2.23 g/t gold (see Figures 8 and 9 below).

Significant mineralized sections for boreholes LADD018, LADD019, LADD021 and LADD022 are summarised in the table below:

Borehole NumberFrom (m)To (m)Intersected
Width (m)
Grade (g/t) Au
LADD018 93.34 113.70 20.36 0.93
LADD018 152.48 178.20 25.72 2.26
LADD019 4.57 11.60 7.03 2.13
LADD021 75.21 88.17 12.96 2.09
LADD021 99.74 106.00 6.26 1.09
LADD021 144.78 160.51 15.73 5.28
LADD021 including 144.78 149.78 5.00 13.70
LADD022 20.50 42.00 21.50 2.23
LADD022 including 25.50 34.00 8.50 4.23

Note:  It is estimated that the true widths of the mineralised sections for core holes LADD018, LADD019, LADD021 and LADD022 are, respectively, 75%, 65%, 73% and 58% of the intersected widths in the above table. In addition, the two holes that intersected grade closest to surface, LADD019 and LADD022, experienced poor associated core recoveries in places, in which case, core loss material was assigned zero grade.

Figure 8:  Adumbi Deposit Longitudinal Section Looking Northeast with Drill Hole Grade (g/t) x True Thickness (Metre) Product Contours

Figure 8: Adumbi Longitudinal Section Looking Northeast with Drill Hole (Grade x Metre) [map]

Figure 9: Geological Cross Section A-B

Figure 9:  Geological Cross Section A-B  [map]

Additional Targets of Interest in Close proximity to Adumbi

At the Kitenge and Manzako deposits (Inferred resources of 1.68 million tonnes grading 5.8 g/t Au, equivalent to 313,000 ounces of gold), additional drilling may also be undertaken to further define and increase the inferred mineral resources at these deposits.

In addition, two undrilled targets have been outlined close to the Adumbi deposit. Both these target areas were identified from the compilation and interpretation of previous, historical exploration data including soil geochemistry, rock chip and channel sampling. At Mambo Bado, 1.5 kilometres northwest of the Adumbi deposit, a prominent geochemical gold in soil anomaly is located on an extensional, E-W structural jog along the 14-kilometre northwest trending mineralized shear. Two kilometres south of the Adumbi deposit, at Lisala, altered and brecciated BIF with anomalous rock sampling requires further follow up with gridding, soil sampling and additional channel sampling.

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