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STAR - ORION SOUTH DIAMOND PROJECT SIGNIFICANT PROPORTIONS OF TYPE IIa DIAMONDS PRESENT AT STAR AND ORION SOUTH George H. Read, P. Geo., Senior Vice P resident Exploration and Development of Star Diamond Corporation (“Star

Marketing Announcement

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NEWS RELEASE March 04, 2019

TSX: DIAM Saskatoon, Saskatchewan

STAR - ORION SOUTH DIAMOND PROJECT

SIGNIFICANT PROPORTIONS OF TYPE IIa DIAMONDS PRESENT AT STAR AND ORION SOUTH

George H. Read, P. Geo., Senior Vice P resident Exploration and Development of Star Diamond Corporation (“Star

Diamond” or the “Corporation”) is pleased to announce that the Corporation has completed a major study into

the abundance of Type IIa diamonds in the diamond parcels recovered from t he Star and Orion South Kimberlites

located within the Corporation’s Star - Orion South Diamond Project , in the Fort à la Corne diamond district of

central Saskatchewan, Canada, on mineral dispositions held 100 percent by Star Diamond . This study confirms

that unusually high proportions of Type I Ia diamonds are present in both the Star (26.5 percent ) and the Orion

South (12.5 percent) kimberlites. This study confirms and augments an earlier study of Type IIa diamonds in the

Star Kimberlite (see News Release dated June 09, 2010).

Type IIa diamonds are very rare and account for approximately less than 2 percent of all natural rough diamonds

mined from kimberlites. Only a small number of active diamond mines regularly produce Type IIa diamonds with

the most impo rtant of these mines being Letseng-la-Terae (Letseng Mine) in the Kingdom of Lesotho. While

Letseng is a low grade (1.5 -3 cpht) kimberlite , it is probably the most prolific source of large high -value Type IIa

diamonds, which contribute to making Letseng a highly economic deposit. The 2010 study on plus 2.7 carat

diamonds from Star demonstrate s that the Star Kimberlite has a similar proportion of Type IIa diamonds to

Letseng.

The Type IIa diamond counts and the percentage of Type IIa diamonds for the major Star and Orion South

kimberlite units are documented in the table below.

Star Kimberlite (Diamonds +11 DTC (0.32 carats) to >10.8 carats)

Geological Unit

Number of Diamonds

Typed

Number of Type IIa

Diamonds

Percentage Type IIa

Diamonds

Early Joli Fou (EJF) UG 3,713 986 26.6

Pense (PPK) UG 722 205 28.4

Cantuar (CPK) UG 961 240 25.0

Total 5,396 1,431 26.5

Orion South Kimberlite (Diamonds +11 DTC (0.32 carats) to >10.8 carats)

Geological Unit

Number of Diamonds

Typed

Number of Type IIa

Diamonds

Percentage Type IIa

Diamonds

Early Joli Fou (EJF) UG 1,118 125 11.2

Early Joli Fou (EJF) LDD 445 66 14.8

Pense (P2) UG 309 43 13.9

Total 1,872 234 12.5

UG (Underground Sample) LDD (Large Diameter Drill Sample)

As can be seen from the table above, a significant number of diamond s, from each of the major kimberlite

lithologies within both Star and Orion South , have been analysed and typed. The diamonds analysed represent a

spectrum of diamond sizes from +11 DTC (+0.32 carats) through all of the large stones, up to diamonds of nearly

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50 carats. The largest Type IIa diamonds ide ntified include a 49.09 carat stone from Star and a 32.35 carat stone

from Orion South. The most valuable of the Type IIa diamonds from Star is the 11.96 carat diamond valued at

US$11,333 per carat and the most valuable of the Type IIa diamonds from Orion South is the 15.88 carat diamond

valued at US$2,800 per carat.

Type IIa diamonds contain no nitrogen or boron impurities and are frequently either top white colours (D, E, F or

G) or an y shade of brown. Many pink and brownish -pink diamonds are also Type IIa. Type IIa diamonds usually

have anhedral crystal shape and exhibit a range of elongated, distorted or irregular morphologies. Most

importantly, many high -value, top colour, large spec ials (greater than 10.8 carats) are Type IIa diamonds, which

include all ten of the largest known rough diamonds recovered worldwide, from the 726 carat Jonker to the 3,106

carat Cullinan.

The coarse diamond size frequency distribution for the Star Kimbe rlite diamond populations (particularly the

Cantuar and Early Joli Fou kimberlite units), combined with this significant proportion of Type IIa diamonds,

strongly suggests the potential for the recovery of large (plus 100 carat), high quality diamonds.

Statistics on the proportions of Type IIa diamonds produced by diamonds mines are not freely available. However,

Bowen et al (2009) published Type IIa FTIR measurements for 484 plus two carat diamonds from the Letseng

Diamond Mine. The Letseng Mine has a lo w grade of some 1 .5 to 3 cpht but is highly economic as a result of its

unusually high average diamond price (US$2,131 per carat in 2018). Letseng accounts for some 30 percent of the

world market share of diamonds greater than 25 carats and has produced so me of the biggest gem quality

diamonds recovered in the past number of years including the 910 carat Lesotho Legend, 603 carat Lesotho

Promise, the 550 carat Letseng Star, the 493 carat Letseng Legacy and the 478 carat Light of Letseng. These are all

Type IIa diamonds. The Karowe Mine of Lucara Diamond Corp . has also produced some record Type IIa diamonds

in the past few years, notably the 1,109 carat L esedi La Rona, which is the second largest gem diamond ever

recovered, and the 813 carat Constellation, which was sold for the record price of US$63.1 million.

Fourier Transform Infrared (FTIR) Spectrometry is used to determine the concentration and aggregation state of

nitrogen within the diamonds using industry standard methods. All analyses of nitrogen content and aggregation

state were carried out at the Saskatchewan Research Council’s ( “SRC”) high security diamond facility, with 24 -

hour video surveillance. The SRC ’s Geoanalytical Laboratories is accredited to the ISO/IEC 17025 standard by the

Standards Council of Canada as a testing laboratory.

Senior Vice President Exploration & Development, George Read, states: “The presence of a significant proportion

of Type IIa diamonds in the Star and Orion South Kimberlites greatly increases the potential for the r ecovery of

large (plus 100 carat), high -value diamonds. Analysis of the Star and Orion South diamond evaluation parcels

indicated a significant proportion of Type IIa diamonds, some of which are top white in colour. The presence of

two high -value diamond groups (octahedra and Type IIa) greatly strengthens the future potential production

diamond pricing from the Star and Orion South Kimberlites.”

Star Diamond Corporation is a Canadian based corporation engaged in the acquisition, exploration and

development of mineral properties. Shares of the Corporation trade on the TSX Exchange under the trading

symbol “DIAM”. The Corporation’s Fort à la Corne kimberlites (including the Star - Orion South Diamond Project ,

or “Project”) are located in central Saskatchewan in close proximity to established infrastructure, including paved

highways and the electrical power grid, which provide significant advantages for future mine development. Rio

Tinto Exploration Canada Inc . (“RTEC”) refers to Star Diamond’s mineral disposit ions in the Fort à la Corne

diamond district as Project FalCon.

All technical information in this press release has been prepared under the supervision of George Read, Senior

Vice-President of Exploration and Development, a registered Professional Geoscientist in the Provinces of

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Saskatchewan and British Columbia and Mark Shimell, Project Manager, a registered Professional Geoscientist in

the Province of Saskatchewan, who are the Corporation’s “Qualified Persons” under the definition of NI 43-101.

References (Available on Corporation’s website)

Bowen, D.C. Ferraris, R.D. Palmer, C.E. and Ward, J.D. (2009) On the unusual characteristics of the diamonds

from Letseng-la-Terae kimberlites, Lesotho. Lithos Vol. 112S pp.767 – 774.

Breeding, C.M. and Shigley, J.E. (2009) The “Type” classification system of diamonds and its importance in

gemology. Gems & Gemology Vol. 45 No. 2 pp. 96 – 111

Caution Regarding Forward-Looking Statements

This news release contains forward -looking statements as defined by certain securities laws, including th e "safe harbour" provisions of

Canadian securities legislation and the United States Private Securities Litigation Reform Act of 1995. Forward -looking information is often,

but not always, identified by the use of words such as "anticipate", "believe", "ex pect", "plan", "intend", "forecast", "target", "project",

"guidance", "may", "will", "should", "could", "estimate", "predict" or similar words suggesting future outcomes or language suggesting an

outlook. In particular, statements regarding the Corporation 's future operations, future exploration and development activities or other

development plans constitute forward- looking statements. B y their nature, statements referring to mineral reserves, mineral resources,

PEA or TFFE constitute forward -looking statements. Forward-looking statements contained or implied in this press release include, but are

not limited to, the potential proportion of Type IIa diamonds in the Star and Orion South kimberlites and the potential for the recovery of

large high quality diamonds.

These forward-looking statements are based on the Corporation's current beliefs as well as assumptions made by and information currently

available to it and involve inherent risks and uncertainties, both general and specific.

Risks exist that forw ard-looking statements will not be achieved due to a number of factors including, but not limited to, developments in

world diamond markets, changes in diamond prices, risks relating to fluctuations in the Canadian dollar and other currencies relative to t he

US dollar, changes in exploration, development or mining plans due to exploration results and changing budget priorities of the Corporation

or its partners, the effects of competition in the markets in which the Corporation operates, the impact of chang es in the laws and

regulations regulating mining exploration, development, closure, judicial or regulatory judgments and legal proceedings, oper ational and

infrastructure risks and the additional risks described in the Corporation's most recently filed Ann ual Information Form, annual and interim

MD&A. The Corporation's anticipation of and success in managing the foregoing risks could cause actual results to differ mate rially from

what is anticipated in such forward-looking statements.

Although management c onsiders the assumptions contained in forward- looking statements to be reasonable based on information

currently available to it, those assumptions may prove to be incorrect. When making decisions with respect to the Corporation , investors

and others shoul d not place undue reliance on these statements and should carefully consider the foregoing factors and other

uncertainties and potential events. Unless required by applicable securities law, the Corporation does not undertake to updat e any

forward-looking statement that is made herein.

For further information: [email protected] or (306) 664-2202

www.stardiamondcorp.com

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