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Standard Lithium Announces Maiden Inferred Resource of 802,000 Tonnes LCE at South-Western Arkansas Tetra Project

Resource Estimates

STANDARD LITHIUM ANNOUNCES MAIDEN INFERRED RESOURCE OF

802,000 TONNES LCE AT SOUTH-WESTERN ARKANSAS TETRA PROJECT

28th January 2019 – Vancouver, BC – Standard Lithium Ltd.(“Standard Lithium” or the

“Company”) (TSXV: SLL) (OTCQX: STLHF) (FRA: S5L), is pleased to report a maiden lithium

resource statement for its approximately 30,000 acre Project (aka TETRA Project) in the south-

western region of Arkansas, USA (the “Property”; see Company news release dated 8th Jan

2018). The maiden resource report, detailed in Table 1 below, includes 802,000 metric tonnes

of lithium carbonate equivalent (LCE) at the Inferred Resource category (see notes [1], [4] and

[5] below). Combined with Standard Lithium’s other project in Southern Arkansas (Lanxess

Property; see news dated 14 th November 2018), this results in a total combined Arkansas

lithium brine resource of 3,888,000 tonnes LCE.

Robert Mintak, CEO said “This combined project in Southern Arkansas positions us as the

largest lithium brine resource in the US; a significantly expanding market that currently relies on

imports of foreign lithium. ” Dr. Andy Robinson, President and COO of Standard Lithium

continued “Our collaboration with TETRA Technologies was fundamental in allowing Standard

Lithium to gain a meaningful foothold in the south-west Arkansas Project area, and this maiden

resource estimate is validation of the high resource potential we identified in this highly

prospective region. We look forward to tighter definition of this resource and developing its

potential in parallel with the Lanxess property.”

Table 1 – South-Western Arkansas Lithium Brine Project Inferred Resource Statement

Upper Smackover

Formation

Middle Smackover

Formation

Total (and

main

resource)

Parameter

South

Resource

Area

North

Resource

Area

South

Resource

Area

North

Resource

Area

Aquifer Volume (km3) 2.49 3.65 0.60 0.93 7.66

Brine Volume (km3) 0.25 0.36 0.06 0.09 0.76

Average lithium

concentration (mg/L) 399 160 399 160 199

Average Porosity 10.1 % 10.1 % 10.3 % 10.3 % 10.1 %

Total Li resource (as

metal) metric tonnes 78,000 44,000 18,000 11,000 151,000

(see notes [4] & [5]

below)

Total LCE resource

(metric tonnes)

(see notes [4] & [5]

below)

413,000 233,000 98,000 59,000 802,000

Notes:

[1] Mineral resources are not mineral reserves and do not have demonstrated economic viability.

There is no guarantee that all or any part of the mineral resource will be converted into a mineral reserve.

[2] Numbers may not add up due to rounding.

[3] The resource estimate was completed and reported using a cut-off of 50 mg/L lithium.

[4] The resource estimate was developed and classified in accordance with guidelines established

by the Canadian Institute of Mining and Metallurgy. The associated Technical Report was completed in

accordance with the Canadian Securities Administration’s National Instrument 43-101 and all associated

documents and amendments. As per these guidelines, the resource was estimated in terms of metallic

(or elemental) lithium.

[5] In order to describe the resource in terms of ‘industry standard’ lithium carbonate equivalent, a

conversion factor of 5.323 was used to convert elemental lithium to LCE.

The TETRA Project lithium brine Inferred Resource, as reported, is contained within the Upper

and Middle facies of the Smackover Formation, a Late Jurassic oolitic limestone aquifer system

that underlies the entire Property. This brine resource is in an area where there is localised oil

and gas production, and where brine is produced as a waste by-product of hydrocarbon

extraction. The data used to estimate and model the resource were gathered from active and

abandoned oil and gas production wells on or adjacent to the Property.

The resource underlies a total of 807 separate brine leases and eight brine mineral deeds which

form a patchwork across Columbia and Lafayette Counties in south-western Arkansas. The

Property consists of 11,033 net hectares (27,262 net acres) leased by TETRA, and the resource

estimate was only modelled for that footprint.

The resource area is split into the northern and southern resource zones, where a fault system

is interpreted to act as a divide between the two areas (although there is hydrogeological

continuity in the resource zone across the fault system). In general, the Upper and Middle

Smackover formations are slightly thinner, with lower lithium grades in the northern zone, and

slightly thicker with higher lithium grades in the southern zone. The depth, shape, thickness and

lateral extent of the Smackover Formation were mapped out in a 3D model using the following

data:

 2,444 wells drilled into the subsurface in the general TETRA Property area. Of

these, 2,041 wells were deep enough (2,135 m, or 7,000 feet) to penetrate the

Upper Smackover Formation;

 104 wells had electric logs available within the TETRA Property that included the top

of the Upper Smackover Formation;

 32 wells had electric logs available within the TETRA Property that included the

base of the Upper Smackover Formation; and,

 19 wells had electric logs available within the TETRA Property that included the

base of the Middle Smackover Formation.

In addition, hardcopy prints of 20 proprietary regional seismic lines totaling over 200 line-km

(over 125 line-miles) were procured, scanned, rasterized and loaded into Kingdom® seismic and

geological interpretation software.

The porosity and permeability data used to characterize the Smackover Formation hydrological

model included:

 Historical effective porosity measurements of more than 1,935 Smackover Formation

core samples that yielded an average effective porosity of 14.3%;

 Historical permeability data that vary from <0.01 to >5,000 millidarcies (mD) with an

average of 338 mD;

 515 core plug samples from oil and gas wells within the Upper and Middle Smackover

Formations at the TETRA Property were analysed for permeability and porosity and

yielded an overall average permeability of 53.3 mD and a total porosity of 10.2%; and,

 3,194 Smackover Formation total porosity values based on LAS density/porosity logs

from 29 wells within, and/or adjacent to, the TETRA Property that have an average total

porosity of 9.2%.

With respect to the resource estimation, a statistical review of the capped and declustered

effective porosity measurements collected within the Upper and Middle Smackover formations

resulted in average porosity values of 10.1% and 10.3% for the Upper and Middle Smackover

formations, respectively.

Representative in-situ brine geochemistry was assessed using eight lithium brine samples taken

from wells re-entered by Standard Lithium in 2018, and was supplemented by four historical

samples. These data yielded an average lithium grade of 160 mg/L in the northern resource

zone and 399 mg/L in the southern resource zone. Sample quality assurance and quality

control was maintained throughout by use of sample blanks, duplicates and standard ‘spikes’,

and by using an accredited, independent laboratory, with a long history of analysing very high

salinity lithium brines.

Resource Estimation Methodology

The resource estimate was completed by Independent qualified person (QP) Mr. Roy Eccles

M.Sc. P. Geol. of APEX Geoscience Ltd., assisted by other Independent QP’s; Mr. Warren

Black M.Sc. P. Geo. of APEX Geoscience Ltd. (resource modelling), Mr. Kevin Hill B.Sc. P.

Geo. Hill Geophysical Consulting (geology), and Mr. Kaush Rakhit M.Sc. P. Geol. of Canadian

Discovery Ltd (hydrogeology). The resource estimate of the lithium brine at the TETRA

Property is classified as an “Inferred” Mineral Resource and was developed and classified in

accordance with guidelines established by the Canadian Institute of Mining and Metallurgy. The

associated Technical Report was completed in accordance with the Canadian Securities

Administration’s National Instrument 43-101 and all associated documents and amendments.

Quality Assurance

The resource evaluation report was completed by the Independent Qualified Persons as

described above, with Roy Eccles P. Geol. as the lead author. Raymond Spanjers, Registered

Professional Geologist (SME No. 3041730), is a qualified person as defined by NI 43-101, and

has supervised the preparation of the scientific and technical information that forms the basis for

this news release. Mr. Spanjers is not independent of the Company as he is an officer in his

role as Vice President, Exploration and Development.

Future Target for Exploration

A Future Target for Exploration (FTE) was also developed which considered the additional

resource which may be present if the lease areas were ‘filled-in’ and the total footprint of the

Project were unitised as a brine-production unit in the future; this FTE considered that an

additional 86,000 to 160,000 tonnes LCE may be present under the total Project footprint if

unitisation were applied for and approved. The potential quantity and grade of the FTE is

conceptual in nature. It is uncertain if Standard Lithium will acquire the leases being delineated

as a future target of exploration and it is uncertain if a mineral resource estimate including the

leases in question will ever be delineated.

About Standard Lithium Ltd.

Standard Lithium (TSX: SLL) is a specialty chemical company focused on unlocking the value of

existing large-scale US based lithium-brine resources. The company believes new lithium

production can be brought on stream rapidly by minimizing project risks at selection stage

(resource, political, geographic, regulatory & permitting), and by leveraging advances in lithium

extraction technologies and processes. The Company’s flagship project is located in southern

Arkansas, where it is engaged in the testing and proving of the commercial viability of lithium

extraction from over 150,000 acres of permitted brine operations utilizing the Company’s

proprietary selective extraction technology. The Company is also pursuing the resource

development of over 30,000 acres of separate brine leases located in southwestern Arkansas

and approximately 45,000 acres of mineral leases located in the Mojave Desert in San

Bernardino County, California.

Standard Lithium is listed on the TSX Venture Exchange under the trading symbol “SLL”;

quoted on the OTC - Nasdaq Intl Designation under the symbol “STLHF”; and on the Frankfurt

Stock Exchange under the symbol “S5L”. Please visit the Company’s website at

www.standardlithium.com.

For further information, contact Anthony Alvaro at (604) 240 4793

On behalf of the Board,

Standard Lithium Ltd.

Robert Mintak, CEO & Director

Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in policies of

the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release. This

news release may contain certain “Forward-Looking Statements” within the meaning of the United States

Private Securities Litigation Reform Act of 1995 and applicable Canadian securities laws. When used in

this news release, the words “anticipate”, “believe”, “estimate”, “expect”, “target, “plan”, “forecast”, “may”,

“schedule” and other similar words or expressions identify forward-looking statements or information.

These forward-looking statements or information may relate to future prices of commodities, accuracy of

mineral or resource exploration activity, reserves or resources, regulatory or government requirements or

approvals, the reliability of third party information, continued access to mineral properties or infrastructure,

fluctuations in the market for lithium and its derivatives, changes in exploration costs and government

regulation in Canada and the United States, and other factors or information. Such statements represent

the Company’s current views with respect to future events and are necessarily based upon a number of

assumptions and estimates that, while considered reasonable by the Company, are inherently subject to

significant business, economic, competitive, political and social risks, contingencies and uncertainties.

Many factors, both known and unknown, could cause results, performance or achievements to be

materially different from the results, performance or achievements that are or may be expressed or

implied by such forward-looking statements. The Company does not intend, and does not assume any

obligation, to update these forward-looking statements or information to reflect changes in assumptions or

changes in circumstances or any other events affections such statements and information other than as

required by applicable laws, rules and regulations.