Diatreme Resources : Resource Grows to 200Mt Across High-Grade Silica Projects

ASX
ANNOUNCEMENT
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17 March 2022
use	Resource Base Grows to ~200Mt Across High-Grade Silica Projects
• Significant expansion to Inferred Mineral Resource for Diatreme's Si2 North Project, increasing by 134%
	from 53 million tonnes (Mt) to 124 Mt @ 99.33% silica (SiO2)
personal	• Si2 North remains open to southeast, with potential for additional drilling to identify further significant
extensions to silica resource
• Drilling results indicate dunes up to 40m thick, averaging 14m, covering area of approximately 556 ha
• Diatreme assessing optimal approaches for development over entire Northern Regional Project area,
including mining lease pre-lodgement discussions with relevant stakeholders and government agencies
• Material step change in resource inventory to total of 199.5 Mt silica now defined in resources, across suite
of high-grade silica projects and amid continued growth in demand from Asia's booming solar PV industry.

Emerging silica sands explorer and high purity silica producer, Diatreme Resources Limited (ASX:DRX) (the Company) continues to expand its high-gradesilica sand resource in North Queensland, North of Cooktown ,with the Company's Si2 North Project resource recording a significant increase of around 134% to 124 Mt.

Located within the Northern Resource Project (NRP) of Diatreme's Cape Bedford (EPM17795) exploration tenement, Si2 North represents a major and additional new project to the Company's existing silica sand reserve at its Galalar

ForSilica Sand Project (GSSP), which contains an estimated 75.5 Mt (refer ASX release 20 September 2021).

The Galalar and Si2 North projects deliver a total resource estimated at 199.5 Mt, providing a large resource base in a stable and ESG compliant jurisdiction amid increasing demand growth from Asia's booming solar PV industry.

Welcoming the latest upgrade, Diatreme's CEO Neil McIntyre said: "This latest huge expansion now starts to show the enormous scale of our silica sand resources now standing at circa 200 million tonnes across both the Galalar and Si2 North projects, which will continue to increase as we intensify our exploration efforts across multiple dune systems.

only"Our Galalar Silica Project remains our immediate development priority given its advanced stage, however having this second exceptional and growing high-grade resource will add to our project development pipeline in the medium term.

"Diatreme also has an important role to play regionally providing long-term and sustainable economic benefits for the local communities, while supporting the world's clean energy future."

useThe expanded Inferred Mineral Resource was estimated by independent industrial minerals mining engineering consultants Ausrocks Pty Ltd (refer attached summary report). The additional resources confirm the target Si2 dune y tem has the potential to host significant silica sand resources, as incremental exploration has increased the resource size significantly.

Diatreme's intention is to examine the resources underpinning project economics and review lodgement of a mining ease application (MLA) covering the northern section of the tenement. This will potentially facilitate the "fast

tr cking" of a second independent major high purity silica operation, with the Si2 North Project benefitting from its proximity to the existing State-owned Cape Flattery port operations (Ports North owned).

Expanded Inferred Resource

A drilling program was undertaken in November 2021, with 47 vacuum drillholes for a total of 1,055.6m used to define this Maiden Inferred Mineral Resource Estimate in accordance with the JORC Code (2012). A further drill program leading to this expanded mineral resource estimate was carried out in December 2021. The drill program comprised 33 vacuum drill holes totalling 919.3m.

Table 1: Expanded Inferred Resource Estimate - Si2 North Project, March 2022

		Resource			Silica Sand			SiO2			Fe2O3			TiO2			Al2O3			LOI		Total		Silica			Density			Cut-off Grade
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		Category			(Mt)			(%)			(%)			(%)			(%)			(%)				Sand					SiO2 (%)
																			(t/m )
																								(Mm3)
		Inferred		124		99.33		0.11		0.15		0.08		0.12		99.85	77.6		1.6		98.5
For

Note: Under the JORC Code, 2012 Edition an Indicated Mineral Resource is that part of a Mineral Resource for which quantity, grade (or quality), densities, shape and physical characteristics are estimated with sufficient confidence to support mine planning and evaluation of the deposit's economic viability. An Inferred Mineral Resource has a lower level of confidence than an Indicated or Measured Mineral Resource.

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Fig 1: Si2 North Project Resource Overview

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Cape

Flattery

Port

Figure 2: Si2 North Prospect Overview - Regional Setting

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2022 Project Development
Diatreme is targeting the following next steps for the NRP, including the Si2 North deposit:
	•Diatreme is continuing to drive exploration and project development efforts though the 2022 wet season,
use	focussed on the PLT and Si2 North dune systems which are located within the NRP area. The focus is on
multiple resource definition over a large area located immediately to the south west of the CFSM mine.
•Preliminary engineering scoping is determining optimal paths to permitting and potential development in the
	area. This will be factored into additional investigation of the Si2 North deposit, including solutions on
	infrastructure and export leveraged to the Cape Flattery Port.
personal	• Bulk sample metallurgical test work on Si2 North will determine amenability to processing utilising Diatreme's
case.
	Galalar optimised silica product processing criteria. This targets assessment and delivery of a high value low
	iron, high purity silica product.
	• Preparation of Mining Lease Applications for this northern section of the tenement, aligned to appropriate
	solutions for infrastructure development and export, with the aim of fast tracking a second major high purity
	silica operation.
	• Undertaking relevant logistics and economics studies as appropriate to determine the economic development

This announcement is authorised for release by the Board of Directors of the Company.

Neil McIntyre	Wayne Swan
Chief Executive Officer	Chairman
For
Contact - Mr Neil McIntyre - Ph - 07 33972222
Website - diatreme.com.au
E-mail - [e-mail]
or media queries, please contact:
Anthony Fensom, Republic PR
[e-mail]
Ph: [phone]

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