Newfield Resources Limited (Newfield) announced an operational update in relation to its Tongo Diamond Mine Development in Sierra Leone (Tongo Mine Development or Tongo). Total underground development has now exceeded 1kilometre - 1,127m of waste and kimberlite development has been achieved to date. Development activity is currently focussed on the continuation of the Kundu decline, Level-1 rock and fissure drives and the ventilation raise from the Kundu Return Airway (RAW).

The fissure drives and the development off the ventilation raise will enable access to the ore body and the establishment of the first mining stopes and signal the transition of Newfield from an explorer and project developer to a producer. The development of the Return Air Way (RAW) on Kundu Segment A has passed the point where the ventilation raise can commence. The RAW has now been developed some 245m and blasting in an easterly direction will continue on-reef to give top level access to the planned stope mining from Level-1 located below the RAW.

This development will continue to provide kimberlite ore for processing until such time as the first mining stopes come into production ­ scheduled for June 2022. Blasting of the 4m x 4m Kundu decline and has now passed the point where the first mining level rock drive is being established. Some 225m of decline development has been completed.

The decline has progressed 32m beyond the break away for the Level-1 rock drive and is planned to continue to the northwest and then turn to the southwest to access the Level-1 development of the Kundu Segment B and C dyke segments. The Level-1 rock drive to access segment A East of the dyke system has turned off the Kundu decline where 34m has been developed so far. The first crosscut breakaway to access ore was blasted after 16m and intersected kimberlite during February 2022, ahead of the scheduled date of late March 2022.

On-reef fissure drive development is now in progress which will in turn allow the establishment of the first raise and mining stope faces. Processing of the kimberlite ore recovered from the on-reef Kundu RAW development continues to yield encouraging diamond grades and quality diamonds. Initial in-house observation estimates that 80% of the diamond recoveries are in the gem quality category, with the larger diamond recovered being a 9.6 carat gem.

The photographs below are pictures of some gem quality stones recovered to date, and notably the shapes and quality are in line with the expectations of run of mine production as seen during the sampling phase. Many diamonds exhibit excellent crystal shapes with top colour and clarity characteristics. Although volume of ore processed to date is relatively small, the results are consistent with, or higher than, the estimated mineral resource grade and value of that area of the Kundu Segment A resource.

In addition to the run of mine processing activities, two controlled bulk samples have been processed to calculate the actual recovered grade from mining and processing, versus the 2019 resource model grades. These samples have been mined from the ongoing Kundu Segment A RAW development and the carat recoveries reconciled directly with those segments of kimberlite in the resource block model, which has grades assigned on a 10m x 10m x 1m block basis across the declared resource.