Osisko Development Expands and Delineates New High Grade Vein Corridors ON Barkerville Mountain’S Lowhee Zone BM-21-015 Intersects 6.26 G/T GOLD over 7.60 Meters
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OSISKO DEVELOPMENT EXPANDS AND DELINEATES NEW HIGH GRADE VEIN
CORRIDORS ON BARKERVILLE MOUNTAIN’S LOWHEE ZONE
BM-21-015 INTERSECTS 6.26 G/T GOLD OVER 7.60 METERS
MONTREAL, May 19, 2021 – Osisko Development Corp. (“Osisko Development” or the “ Company”) (TSX.V:
ODV) is pleased to announce drilling results from the 200,000-meter 2021 exploration and category conversion
drill program campaign at its Cariboo Gold Project (“ Cariboo Project”) in central British Columbia. A total of ten
diamond drill rigs are currently active on the Cariboo Project.
Lowhee Zone Overview
Two rigs currently operating on Lowhee Zone located on Barkerville Mountain.
Recent results include holes BM-21-001 to BM-21-018.
Mineralized vein corridors are currently defined along 650 m eters strike by 350 m eters in the sandstone
to a depth of 275 meters and is open in all directions.
Lowhee is interpreted to be the strike extension of Cow Mountain as shown in recent results.
Based on the Mineral Resource Estimate dated October 5, 2020, at a cut -off grade of 2.1 0 g/t Au, the
Lowhee Zone contains 46,000 oz in the indicated category and 105 ,000 oz Au in the inferred category
based on only 23 drill holes.
A total of 73 drill holes have since been drilled in the Lowhee Zone.
Detailed drilling results, a drill hole location plan map and vertical long section is presented at the end of
this release.
Recent Drilling Highlights:
13.22 g/t Au over 2.60 meters in hole BM-21-001
6.14 g/t Au over 6.55 meters in hole BM-21-002 including
43.70 g/t Au over 0.60 meter in hole BM-21-002
70.90 g/t Au over 1.00 meter in hole BM-21-013
6.26 g/t Au over 7.60 meters in hole BM-21-015
7.97 g/t Au over 4.05 meters in hole BM-21-016 including
58.80 g/t Au over 0.50 meter in hole BM-21-016
41.39 g/t Au over 1.10 meters in hole BM-21-017 including
70.20 g/t Au over 0.60 meter in hole BM-21-017
Chris Lodder, President of Osisko Development commented, “ With these initial drill results, Lowhee extends the
Cariboo Gold Project resource footprint to beyond 4 km of strike length demonstrating near continuous vein
corridor style mineralization from Mosquito Creek to Lowhee, open in along strike and at depth.”
Mineralized quartz veins on Cariboo are overall sub-vertical dip and northeast strike. Vein corridors are defined as
a high-density network of mineralized quartz veins within the axis of the last folding event’s folds and hosted within
a brittle meta-sandstone or calcareous meta-sandstone. Vein corridors are modelled at a minimum thickness of 2
meters and average about 4.5 meters true width. Individual mineralized veins within these corridors have widths
varying from centimeters to several meters and strike lengths from a few meters to over 50 meters. These corridors
have been defined from surface to a vertical depth averaging 300 meters and remain open for expansion at depth
and along strike. Gold grades are intimately associated with quartz vein -hosted pyrite as well as pyritic, intensely
silicified wall rock haloes in close proximity to the veins.
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True widths are estimated to be 60% to 75% of reported core length intervals. Intervals not recovered by drilling
were assigned zero grade. Top cuts have not been applied to high grade assays. Complete assay highlights are
presented in Table 1, drill hole locations are listed in Table 2.
Figure 1: Cariboo Deposit Areas with drill locations.
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Figure 2: Lowhee detail area with drill intercept highlights
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Figure 3: Lowhee Zone Long Section
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Qualified Persons
Per National Instrument 43-101 Standards of Disclosure for Mineral Projects, Maggie Layman, P.Geo. Vice
President Exploration of Osisko Development Corp., is a Qualified Person and has prepared, validated,
and approved the technical and scientific content of this news release.
Quality Assurance – Quality Control
Once received from the drill and processed, all drill core samples are sawn in half, labelled and bagged.
The remaining drill core is subsequently stored on site at a secured facility in Wells, BC. Numbered security
tags are applied to lab shipments for chain of custody requirements. Quality control (QC) samples are
inserted at regular intervals in the sample stream, including blanks and reference materials with all sample
shipments to monitor laboratory performance. The QAQC program was designed and app roved by Lynda
Bloom, P.Geo. of Analytical Solutions Ltd.
Drill core samples are submitted to ALS Geochemistry’s analytical facility in North Vancouver, British
Columbia for preparation and analysis. The ALS facility is accredited to the ISO/IEC 17025 sta ndard for
gold assays and all analytical methods include quality control materials at set frequencies with established
data acceptance criteria. The entire sample is crushed, and 250 grams is pulverized. Analysis for gold is
by 50g fire assay fusion with a tomic absorption (AAS) finish with a lower limit of 0.01 ppm and upper limit
of 100 ppm. Samples with gold assays greater than 100 ppm are re-analyzed using a 1,000g screen metallic
fire assay. A selected number of samples are also analyzed using a 48 mult i-elemental geochemical
package by a 4 -acid digestion, followed by Inductively Coupled Plasma Atomic Emission Spectroscopy
(ICP-AES) and Inductively Coupled Plasma Mass Spectroscopy (ICP-MS).
About Osisko Development Corp.
Osisko Development Corp. is we ll-capitalized and uniquely positioned as a premier gold development
company in North America to advance the Cariboo Gold Project and other Canadian and Mexican
properties, with the objective of becoming the next mid -tier gold producer. The Cariboo Gold Project,
located in central British Columbia, is Osisko Development's f lagship asset with measured and indicated
resources of 21.44 Mt at 4.6 Au g/t for a total of 3.2 million ounces of gold and inferred resource of 21.69 Mt
at 3.9 Au g/t for a total of 2.7 million ounces of gold (see NI 43-101 Technical Report for resource October
5th, 2020). The considerable exploration potential at depth and along strike distinguishes the Cariboo Gold
Project relative to other development assets as does the historically low, all -in discovery costs of US $19
per ounce. The Cariboo Gold Proje ct is advancing through permitting as a 4,750 tonnes per day
underground operation with a feasibility study on track for completion in the second half of 2021. Osisko
Development's project pipeline is complemented by potential near -term production targeted from the San
Antonio gold project, located in Sonora Mexico and early exploration stage properties including the Coulon
Project and James Bay Properties located in Québec as well as the Guerrero Properties located in Mexico.
Osisko Development began trading on the TSX Venture Exchange under the symbol "ODV" on December
2, 2020.
For further information, please contact Osisko Development Corp.:
Jean Francois Lemonde
VP Investor Relations
Tel: 514-299-4926
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Forward-looking Statements
Certain statements contained in this press release may be deemed “forward‐looking statements” within the
meaning of applicable Canadian and U.S. securities laws. These forward ‐looking statements, by their
nature, require Osisko to make certain assumptions and necessarily involve known and unknown risks and
uncertainties that could cause actual results to differ materially from those expressed or implied in these
forward‐looking statements. Forward‐looking statements are not guarantees of performance. Words such
as “may”, “will”, “would”, “could”, “expect”, “believe”, “plan”, “anticipate”, “intend”, “estimate”, “continue”, or
the negative or comparable terminology, as well as terms usually used in the future and the conditional, are
intended to identify forward ‐looking statements. Information contained in forward ‐looking statements is
based upon certain material assumptions that were applied in drawing a conclusion or making a for ecast
or projection, including management’s perceptions of historical trends, current conditions and expected
future developments, results of further exploration work to define and expand mineral resources, that vein
corridors continue to be defined as a h igh-density network of mineralized quartz within the axis of the last
folding event’s folds and hosted within a brittle meta-sandstone or calcareous meta-sandstone and that the
deposit remains open in along strike and at depth, as well as other considerati ons that are believed to be
appropriate in the circumstances. Osisko considers its assumptions to be reasonable based on information
currently available, but cautions the reader that their assumptions regarding future events, many of which
are beyond the c ontrol of Osisko, may ultimately prove to be incorrect since they are subject to risks and
uncertainties that affect Osisko and its business. Such risks and uncertainties include, among others, risks
relating to the ability of exploration activities (inclu ding drill results) to accurately predict mineralization;
errors in management’s geological modelling; the ability of to complete further exploration activities,
including drilling; property and royalty interests in the Cariboo gold deposit; the ability of the Corporation to
obtain required approvals; the results of exploration activities; risks relating to mining activities; the global
economic climate; metal prices; dilution; environmental risks; and community and non -governmental
actions and the response s of relevant governments to the COVID -19 outbreak and the effectiveness of
such responses.
For additional information with respect to these and other factors and assumptions underlying the forward ‐
looking statements made in this news release concerning Osisko Development, see the Filing Statement
available electronically on SEDAR (www.sedar.com) under Osisko Development's issuer profile. The
forward‐looking statements set forth herein concerning Osisko Development reflect management's
expectations as at the date of this news release and are subject to change after such date. Osisko
Development disclaims any intention or obligation to update or revise any forward -looking statements,
whether as a result of new information, future events or otherwise, other than as required by law.
Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in
the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of
this news release. No stock exchange , securities commission or other regulatory authority has
approved or disapproved the information contained herein.
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Table 1: Cariboo Gold Project Lowhee Zone 2021 Length Weighted Drill Hole Gold Composites
HOLE ID FROM M TO (M) LENGTH
(M) AU G/T
BM-21-001 206.20 207.15 0.95 3.22
219.65 222.25 2.60 13.22
INCLUDING 219.65 220.15 0.50 45.40
AND 221.75 222.25 0.50 18.35
226.80 227.95 1.15 3.11
227.95 228.45 0.50 3.55
233.55 234.05 0.50 4.78
251.50 253.00 1.50 6.92
INCLUDING 251.50 252.00 0.50 17.05
BM-21-002 127.25 133.80 6.55 6.14
INCLUDING 127.25 127.75 0.50 8.24
AND 130.55 131.15 0.60 43.70
AND 133.15 133.80 0.65 10.30
194.70 195.20 0.50 9.56
226.50 227.00 0.50 4.41
272.30 275.95 3.65 4.78
INCLUDING 274.80 275.40 0.60 6.86
AND 275.40 275.95 0.55 13.45
304.60 305.10 0.50 7.08
434.95 435.65 0.70 25.70
BM-21-003 42.00 43.15 1.15 7.28
147.80 148.40 0.60 3.63
220.00 220.55 0.55 6.30
238.80 239.55 0.75 16.30
351.00 351.50 0.50 12.95
BM-21-004 135.50 136.50 1.00 4.41
151.00 151.50 0.50 4.65
188.00 188.50 0.50 3.77
189.00 190.00 1.00 3.90
BM-21-005 49.70 51.00 1.30 8.47
141.00 141.50 0.50 5.11
143.95 144.50 0.55 3.50
183.85 184.40 0.55 5.55
359.20 359.80 0.60 5.08
381.55 383.50 1.95 8.88
INCLUDING 381.55 382.90 1.35 11.45
BM-21-006 35.10 35.80 0.70 4.31
38.00 38.50 0.50 8.96
INCLUDING 129.70 130.35 0.65 5.11
AND 131.70 132.35 0.65 4.57
BM-21-007 191.20 191.70 0.50 5.63
206.50 207.00 0.50 6.69
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216.20 216.75 0.55 3.63
234.45 234.95 0.50 5.06
253.80 254.50 0.70 6.19
BM-21-008 143.20 143.70 0.50 7.08
145.20 148.60 3.40 4.83
211.50 213.45 1.95 10.63
INCLUDING 211.50 212.00 0.50 8.25
AND 212.70 213.45 0.75 22.00
BM-21-009 46.50 47.15 0.65 3.96
147.40 152.00 4.60 2.23
INCLUDING 147.40 148.00 0.60 11.25
AND 151.50 152.00 0.50 3.68
173.50 174.00 0.50 7.28
271.65 272.15 0.50 9.75
BM-21-010
NO
SIGNIFICANT
ASSAYS
BM-21-011 40.80 42.85 2.05 2.88
INCLUDING 40.80 41.45 0.65 5.82
315.20 316.00 0.80 4.49
317.25 318.00 0.75 6.94
BM-21-012 153.00 153.70 0.70 8.41
161.90 162.40 0.50 18.15
206.50 207.00 0.50 12.75
BM-21-013 120.25 120.75 0.50 3.33
138.00 139.00 1.00 70.90
148.50 150.00 1.50 5.60
BM-21-014 147.50 148.75 1.25 11.57
INCLUDING 148.25 148.75 0.50 26.20
163.40 164.50 1.10 7.22
INCLUDING 163.40 163.95 0.55 11.25
232.40 232.95 0.55 14.95
BM-21-015 182.90 190.50 7.60 6.26
INCLUDING 182.90 183.50 0.60 15.70
AND 183.50 184.00 0.50 17.00
AND 185.50 186.00 0.50 11.60
AND 189.10 189.95 0.85 22.00
BM-21-016 155.85 156.40 0.55 4.47
163.55 164.10 0.55 6.75
180.50 184.55 4.05 7.97
INCLUDING 183.50 184.00 0.50 58.80
192.60 193.10 0.50 6.38
195.25 196.45 1.20 7.27
203.50 204.50 1.00 21.10
233.75 234.50 0.75 3.99
256.00 256.60 0.60 7.27