Osisko Development Intercepts 443.64 G/T GOLD over 1.19 Meters IN
NYSE | TSXV: ODV NEWS RELEASE
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OSISKO DEVELOPMENT INTERCEPTS 443.64 G/T GOLD OVER 1.19 METERS IN
UNDERGROUND SAMPLING AT TRIXIE, TINTIC PROJECT
Montreal, Québec, December 21, 2023 – Osisko Development Corp. (NYSE: ODV, TSXV: ODV)
("Osisko Development" or the "Company") is pleased to announce drilling and underground chip
sampling results from new development areas as part of its 2023 exploration program at its 100% -
owned Trixie test mine (" Trixie"), within the Company's wider Tintic Project (" Tintic" or the " Tintic
Project"), located in the historic East Tintic Mining District in central Utah, U.S.A.
UNDERGROUND CHIP SAMPLE ASSAY HIGHLIGHTS
Assay highlights include underground chip samples from 79 new development faces at Trixie. Of these,
35 faces had samples with greater than 1.0 grams per tonne (" g/t") gold ("Au") or greater than 50.0
g/t silver (" Ag") values (see Table 1 ). The remaining chip samples returned no significant assays.
Selected assay highlights include:
• 30.85 g/t Au over 1.52 meters ("m") in CH01593 (0.90 troy ounce per short ton (" oz/t") Au
over 5.00 ft)
• 17.93 g/t Au and 128.90 g/t Ag over 1.52 m in CH01594 (0.52 oz/t Au and 3.76 oz/t Ag over
5.00 ft)
• 5.07 g/t Au over 7.01 m in CH01604 (0.15 oz/t Au over 23.00 ft) including
o 16.80 g/t Au over 1.52 m in CH01604 (0.49 oz/t Au over 5.00 ft)
• 443.64 g/t Au over 1.19 m in CH01632 (12.94 oz/t Au over 3.90 ft)
• 23.25 g/t Au and 25.34 g/t Ag over 1.46 m in CH01634 (0.68 oz/t Au and 0.74 oz/t Ag over
4.80 ft)
CHIP SAMPLE SUMMARY
• Chip samples were collected in new development areas in the face and walls of exploration
crosscuts to explore along all domains of the Trixie deposit on the 625 Level, to the north
towards the Trixie Fault and to the south towards the Sioux Ajax Fault (see Figure 2)
• The sampling and drilling results provide support that target areas to the north of Trixie and to
the south down plunge of the T2 structure are mineralized and warrant further follow -up
exploration drilling and sampling.
DRILL ASSAY HIGHLIGHTS
This news release includes assays from eight underground diamond drill ("DD") holes (see Table 2).
Select assay highlights include:
• 8.32 g/t Au and 501.00 g/t Ag over 1.52 m in hole TRXU-DD-23-055 (0.24 oz/t Au and 14.61
oz/t Ag over 5.00 ft)
• 9.43 g/t Au and 239.00 g/t Ag over 1.22 m in hole TRXU -DD-23-056 (0.28 oz/t Au and 6.97
oz/t Ag over 4.00 ft)
• 9.04 g/t Au and 323.00 g/t Ag over 1.52 m in hole TRXU -DD-23-057 (0.26 oz/t Au and 9.42
oz/t Ag over 5.00 ft) including
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o 12.53 g/t Au and 169.00 g/t Ag over 0.76 m in hole TRXU -DD-23-057 (0.37 oz/t Au
and 4.93 oz/t Ag over 2.50 ft)
• 7.46 g/t Au and 301.52 g/t Ag over 2.77 m in hole TRXU -DD-23-059 (0.22 oz/t Au and 8.79
oz/t Ag over 9.10 ft) including
o 14.41 g/t Au and 570.00 g/t Ag over 0.91 m in hole TRXU -DD-23-059 (0.42 oz/t Au
and 16.63 oz/t Ag over 3.00 ft)
DRILL RESULTS SUMMARY
• In 2023, the company completed a total of 6,447 m (21,151 ft) of underground drilling in 73
DD holes at Trixie. To date, assays have been received for 59 DD holes, with assays pending for
the remaining holes.
• One diamond drill rig is currently active underground testing a copper-gold porphyry target,
Trixie West, below the Trixie deposit.
• Approximately 25% of the drilling to date consists of delineation of domains within the area of
the current Trixie MRE (as defined herein) and 75% is exploration drilling adjacent to the area
of the Trixie MRE, including step outs down dip, down plunge and along strike testing for
mineralized structures.
• The focus of these recent holes was to test for mineralization along one of the priority target
areas south on strike from the known T2 domain, towards the Sioux Ajax fault (see Figure 2).
• A new mineral resource estimate (" MRE") for the Trixie deposit is expected to be completed
once all assay results from the 2023 exploration program have been received and surface and
underground mapping data has been integrated.
About Trixie
The Trixie test mine is one of several gold and base metal targets within the larger Tintic Project
consisting of >17,000 acres of patented mining claims and mineral leases within the historic East Tintic
Mining District of Central Utah, U.S.A. The T2 and T4 structures at Trixie show multi-ounce gold grades
associated with high sulphidation epithermal mineralization, structurally controlled and hosted within
quartzites. The T2 structure mineralization consists of native Au, and rare Au-Ag rich telluride minerals
with quartz. The T4 is a mineralized stockwork zone located in the hanging wall of the T2 and is
comprised of Au -Ag rich mineralization in host rock quartzite with quartz -barite-sulphosalt stockwork
veining. Mineralization reports consistent multi-ounce gold grades along the entire strike length.
A 3D model and virtual site tour of Trixie and the wider Tintic Project is accessible on the Company's
VRIFY page at: https://vrify.com/decks/12801.
Information relating to the Tintic Project and the current MRE for the Trixie deposit (the "Trixie MRE")
is supported by the technical report titled "NI 43-101 Technical Report, Initial Mineral Resource Estimate
for the Trixie Deposit, Tintic Project, Utah, United States of America", dated January 27, 2023 (with an
effective date of January 10, 2023) prepared for the Company by independent representatives of Micon
International Limited (the "Tintic Technical Report"). Reference should be made to the full text of the
Tintic Technical Report, which was prepared in accordance with National Instrument 43-101 – Standards
of Disclosure for Mineral Projects ("NI 43 -101") and is available electronically on SEDAR+
(www.sedarplus.ca) and on EDGAR ( www.sec.gov) under Osisko Development's issuer profile and on
the Company's website at www.osiskodev.com.
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Figure 1: Trixie Project Area
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Figure 2: Drill and Chip Sample Plan Map with assay highlights
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Figure 3: Trixie Long Section
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Table 1: Face Chip Sample Length Weighted Assay Composites at Trixie
Site ID Depth from
(m)
Depth to
(m) Length (m) Au (g/t) Ag (g/t) Depth from
(ft.)
Depth to
(ft.) Length (ft.) Au (oz/t) Ag (oz/t)
CH01582 0.61 1.01 0.40 1.03 12.10 2.00 3.30 1.30 0.03 0.35
CH01586 4.57 5.18 0.61 0.72 271.68 15.00 17.00 2.00 0.02 7.92
CH01589 2.90 3.35 0.46 0.72 362.29 9.50 11.00 1.50 0.02 10.57
CH01593 3.05 4.57 1.52 30.85 0.00 10.00 15.00 5.00 0.90 0.00
CH01593 22.86 23.77 0.91 6.62 36.82 75.00 78.00 3.00 0.19 1.07
CH01594 3.05 4.57 1.52 1.20 0.00 10.00 15.00 5.00 0.04 -0.10
CH01594 25.91 27.43 1.52 17.93 128.87 85.00 90.00 5.00 0.52 3.76
CH01596 2.32 2.74 0.43 2.61 111.69 7.60 9.00 1.40 0.08 3.26
CH01599 0.00 1.52 1.52 4.25 23.28 0.00 5.00 5.00 0.12 0.68
CH01603 3.66 3.96 0.30 0.58 65.44 12.00 13.00 1.00 0.02 1.91
CH01604 0.00 7.01 7.01 5.07 0.00 0.00 23.00 23.00 0.15 0.00
CH01604 including 0.00 1.52 1.52 16.80 0.00 0.00 5.00 5.00 0.49 0.00
CH01605 2.38 2.87 0.49 0.58 55.45 7.80 9.40 1.60 0.02 1.62
CH01605 4.27 5.09 0.82 1.41 7.30 14.00 16.70 2.70 0.04 0.21
CH01606 0.00 9.14 9.14 3.20 22.95 0.00 30.00 30.00 0.09 0.67
CH01606 including 7.62 9.14 1.52 3.09 137.71 25.00 30.00 5.00 0.09 4.02
CH01607 0.00 1.77 1.77 2.53 10.79 0.00 5.80 5.80 0.07 0.31
CH01609 2.44 3.35 0.91 4.63 54.41 8.00 11.00 3.00 0.13 1.59
CH01610 0.00 1.46 1.46 6.95 127.73 0.00 4.80 4.80 0.20 3.73
CH01610 0.00 0.49 0.49 10.15 69.15 0.00 1.60 1.60 0.30 2.02
CH01612 0.00 1.52 1.52 12.88 59.97 0.00 5.00 5.00 0.38 1.75
CH01612 including 1.10 1.52 0.43 17.38 78.64 3.60 5.00 1.40 0.51 2.29
CH01617 0.00 1.52 1.52 12.68 0.00 0.00 5.00 5.00 0.37 0.00
CH01621 0.91 2.44 1.52 0.65 70.66 3.00 8.00 5.00 0.02 2.06
CH01625 1.52 4.57 3.05 3.73 45.57 5.00 15.00 10.00 0.11 1.33
CH01625 including 1.52 1.83 0.30 15.74 198.56 5.00 6.00 1.00 0.46 5.79
CH01627 6.55 7.01 0.46 0.58 52.52 21.50 23.00 1.50 0.02 1.53
CH01628 0.00 3.05 3.05 3.86 16.04 0.00 10.00 10.00 0.11 0.47
CH01628 including 0.00 1.52 1.52 6.51 16.11 0.00 5.00 5.00 0.19 0.47
CH01629 2.53 3.05 0.52 0.72 67.17 8.30 10.00 1.70 0.02 1.96
CH01629 4.57 4.72 0.15 0.24 55.42 15.00 15.50 0.50 0.01 1.62
CH01631 0.00 1.52 1.52 9.29 14.78 0.00 5.00 5.00 0.27 0.43
CH01632 0.00 1.19 1.19 443.64 0.00 0.00 3.90 3.90 12.94 0.00
CH01633 0.00 1.43 1.43 2.95 3.43 0.00 4.70 4.70 0.09 0.10
CH01634 0.00 1.46 1.46 23.25 25.34 0.00 4.80 4.80 0.68 0.74
CH01634 including 0.00 0.61 0.61 31.27 39.94 0.00 2.00 2.00 0.91 1.16
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Site ID Depth from
(m)
Depth to
(m) Length (m) Au (g/t) Ag (g/t) Depth from
(ft.)
Depth to
(ft.) Length (ft.) Au (oz/t) Ag (oz/t)
CH01635 0.00 1.52 1.52 1.20 0.00 0.00 5.00 5.00 0.04 0.00
CH01636 5.03 5.36 0.34 0.72 430.99 16.50 17.60 1.10 0.02 12.57
CH01637 8.60 9.14 0.55 2.95 6.75 28.20 30.00 1.80 0.09 0.20
CH01638 0.00 0.73 0.73 0.48 53.72 0.00 2.40 2.40 0.01 1.57
CH01638 2.26 2.99 0.73 1.20 92.08 7.40 9.80 2.40 0.04 2.69
CH01644 0.61 1.52 0.91 1.10 0.00 2.00 5.00 3.00 0.03 0.00
CH01645 0.00 1.52 1.52 1.65 0.00 0.00 5.00 5.00 0.05 0.00
CH01646 0.00 1.52 1.52 1.23 6.34 0.00 5.00 5.00 0.04 0.18
CH01646 7.62 9.14 1.52 1.37 134.93 25.00 30.00 5.00 0.04 3.94
CH01647 1.52 3.05 1.52 7.45 74.05 5.00 10.00 5.00 0.22 2.16
CH01647 including 1.98 2.32 0.34 12.23 91.67 6.50 7.60 1.10 0.36 2.67
CH01648 1.52 3.05 1.52 2.54 9.08 5.00 10.00 5.00 0.07 0.26
CH01648 4.57 6.10 1.52 1.27 10.32 15.00 20.00 5.00 0.04 0.30
CH01652 0.00 1.52 1.52 1.71 43.88 0.00 5.00 5.00 0.05 1.28
CH01652 2.13 3.05 0.91 0.41 62.15 7.00 10.00 3.00 0.01 1.81
Table 2: Drilling Length Weighted Assay Composites at Trixie
Hole ID
Depth
from
(m)
Depth to
(m)
Length
(m)
Au
(g/t)
Ag
(g/t)
Depth
from
(ft.)
Depth to
(ft.)
Length
(ft.)
Au
(oz/t)
Ag
(oz/t) Comments
TRXU-DD-23-052 99.97 101.50 1.52 1.80 12.55 328.00 333.00 5.00 0.05 0.37 Exploration
TRXU-DD-23-053 51.36 53.04 1.68 3.71 41.27 168.50 174.00 5.50 0.11 1.20 Exploration
TRXU-DD-23-054 No Significant Assays Exploration
TRXU-DD-23-055 37.19 40.23 3.05 4.75 264.24 122.00 132.00 10.00 0.14 7.71 Exploration
TRXU-DD-23-055 including 38.71 40.23 1.52 8.32 501.00 127.00 132.00 5.00 0.24 14.61 Exploration
TRXU-DD-23-055 49.56 52.30 2.74 3.26 263.10 162.60 171.60 9.00 0.10 7.67 Exploration
TRXU-DD-23-056 87.48 88.70 1.22 9.43 239.00 287.00 291.00 4.00 0.28 6.97 Exploration
TRXU-DD-23-057 45.72 47.24 1.52 9.04 323.00 150.00 155.00 5.00 0.26 9.42 Exploration
TRXU-DD-23-057 including 45.72 46.48 0.76 12.53 169.00 150.00 152.50 2.50 0.37 4.93 Exploration
TRXU-DD-23-058 No Significant Assays Exploration
TRXU-DD-23-059 35.97 38.74 2.77 7.46 301.52 118.00 127.10 9.10 0.22 8.79 Exploration
TRXU-DD-23-059 including 37.49 38.40 0.91 14.41 570.00 123.00 126.00 3.00 0.42 16.63 Exploration
TRXU-DD-23-059 and 38.40 38.74 0.34 11.60 88.56 126.00 127.10 1.10 0.34 2.58 Exploration
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Qualified Persons
The scientific and technical information contained in this news release has been reviewed and approved
by Maggie Layman, P.Geo., Vice President, Exploration of Osisko Development, and a "qualified person"
within the meaning of NI 43-101.
Face Sampling Methodology
As most structures at Trixie are steeply dipping to the east or west, current sampling procedures are
designed to sample the structure. Chip samples are collected and do not exceed 1.0 m (3 ft.) in length.
The face is washed for safety, and for better iden tification of mineralization, alteration and structures.
The hanging wall and footwall of the structures are marked up on the face and back, samples intervals
are marked up and follow lithological contacts.
Samples are collected in feet and assays are reported in grams per tonne and troy ounce per short ton
gold and silver. Conversions to metric and imperial measurements are rounded to two decimal places.
Quality Assurance (QA) – Quality Control (QC)
All drill core and exploration samples are dispatched to SGS Canada's laboratory in Burnaby, British
Columbia for offsite sample preparation and analysis. Samples are assigned a unique sample ID. All
geological and sampling information is entered into Datamine Fusion database. Core is sawn in half, and
half is sampled. Certified standards and blanks are inserted into all sample dispatches. Samples are
collected by Old Dominion Transportation and dispatched to SGS Canada’s laboratory in Burnaby, British
Columbia. Sample submission forms accompany the samples, and digital copies are emailed to SGS
Canada.
All core sample preparation is completed by SGS Canada, including drying, crushing, and pulverizing of
samples. Analytical assays include gold by 30 gram fire assay with AAS finish (GO_FAA30V10), and gold
overlimits by fire assay with gravimetric finish (GO_FAG30V). Multielement analysis (including silver) is
by four -acid digest with ICP -AES/ICP-MS finish (GE_ICM40Q12). The pulps are returned to Osisko
Development and coarse rejects are disposed after 90 days. Assays are reported to Osisko Development
and then loaded into Datamine Fusion. Quality Assurance -Quality Control samples are checked, and
assays are merged with sample information for future reporting.
Underground face samples are collected by Company geologists from each of the active mining faces,
with samples transported by the geologists from Trixie to the on-site Company laboratory located at the
Burgin administrative complex. Underground samples are dried, crushed to <10 mm and a 250 g split
is taken. The split is pulverized, and a 30 g Fire Assay with gravimetric finish is completed to determine
gold and silver grades, reported in oz/short ton and g/t.
The Company's Burgin laboratory is not a certified analytical laboratory, but the facility is managed by
a qualified laboratory manager with annual auditing by technical staff. Inter -laboratory check assays
using ALS Laboratory as a third -party independent analysis of samples is routinely carried out as part
of ongoing QA/QC work. Certified OREAS QC standards and blanks are inserted at regular intervals in
the sample stream to monitor laboratory performance.
True width determination is estimated to be approximately 0.3 m to 2.4 m (1 to 8 ft.) wide for the T2
structure, approximately 3 m to 25 m (10 to 80 ft.) for the T4 mineralized stockwork zone located in
the hanging wall of the T2 structure and 1.5 m to 3 m (5 to 9 ft.) for the 75-85 structure.