Shefa Yamim Finds High Grade Spinel

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Spinel, Ilmenite, and Garnet added to Gem Box Suite of potential commercial stones

Shefa Yamim Gem Box

Commenting on the results Avi Taub, CEO of Shefa Yamim, said: “Shefa Yamim’s gem-box contains very rare gemstones which will form the basis of jewelry which, once manufactured, will be marketed, due to their provenance, as ‘gemstones from the Holy Land"

Shefa Yamim (LSE: SEFA), a precious stone exploration company in Northern Israel, announces that it has updated its Target Mineral Assemblage (“TMA”), following the results of its 14 bulk sampling campaign at the Kishon Mid-Reach Zone 1. The TMA recovered from the 6,384 tonnes sampling campaign in Zone 1 increased from a total of 5,825.24 carats (“cts”) to a new total of approximately 9,778.15 cts enabling the original TMA to be updated to a predominantly gemstone suite (99.5%) of potentially 9 gemstone minerals, including the new addition of spinel, often found in large crystals. Spinels come in different colours such as red, black, violet, and the very rare blue.

Highlights from Bulk Sampling Campaign at the Kishon Mid-Reach Zone 1

  • Increase in total gemstone minerals to date by 99.5% to 9,778.15 cts
  • Spinel becomes the 9th gemstone to be added to the TMA suite following a recovery of 3,952.91cts
  • Cutting and polishing confirms gemstone quality of garnets, a total of 2,176.77 cts were recovered
  • DMCH Suite renamed to ‘Gem Box’ to reflect the addition of the new gemstone minerals
  • Garnets re-assigned to the ‘Gem Box’ suite from the original HIM suite of heavy minerals made up of garnet, ilmenite, zircon and rutile (“HIM”)
  • Ilmenite greater than or equal to 1mm,was also re-assigned to the ‘Gem Box’ suite from the HIM suite as it is found to be of gemstone quality, a total of 768.86 cts were recovered
  • The revised TMA, dominated by the Gem Box suite, is comprised mainly of minerals that are ≤0.65 cts/stn (85%) with 15% being ≥0.65cts. The largest gems recovered were: Carmel sapphire™ 33.3ct, garnet 13.6ct, sapphire 5.7ct, spinel 6.2ct, hibonite 2.8ct and ruby 1.7ct
  • The overall TMA grade was some 153 cpht (at a bottom screen size of 1 mm), with the grade dominated by 4 Gem Box suite minerals: spinel (69.91 cpht); Carmel sapphire™ (39.36 cpht); garnet (34.09 cpht) and ilmenite (12.06 cpht).

Commenting on the results Avi Taub, CEO of Shefa Yamim, said:

“This is an excellent start to our campaign as we move towards trial mining at the Kishon Mid-Reach Zone 1 and progress with Zone 2. The discovery of a 9th gemstone, Spinel, at our project in northern Israel, coupled with the re-classification of ilmenite and garnet to the newly created ‘Gem Box’, further cements our position as a unique multi-commodity explorer.

“Shefa Yamim’s gem-box contains very rare gemstones which will form the basis of jewelry which, once manufactured, will be marketed, due to their provenance, as ‘gemstones from the Holy Land. We look forward to updating the market in due course.”

RECOVERED GRADES & PRELIMINARY SIZE DISTRIBUTION OF THE TMA SUITE IN ZONE 1, KISHON MID REACH ALLUVIAL PLACER

  • With the “new” gem minerals added to the original “DMCH” suite, viz., garnet, ilmenite and spinel, this higher value collection has been renamed the “Gem Box” suite to reflect the ≥95% gem contribution in Zone 1 of the Kishon Mid Reach alluvial placer.
  • In the revised TMA, only 2 minerals thus fall into the “HIM” industrial category (0.5%): zircon (which may also be a gem at larger sizes) and rutile (Table 1).
  • The revised TMA, dominated by the Gem Box suite, is comprised mainly of minerals that are ≤0.65 cts/stn (85%) with 15% being ≥0.65cts. The largest gems recovered were Carmel sapphire™ 33.3ct, garnet 13.6ct, sapphire 5.7ct, spinel 6.2ct, hibonite 2.8ct and ruby 1.7ct.
  • As Zone 1 has been mapped out as a geologically and geomorphologically “homogenous” section of the Kishon Mid Reach alluvial placer (notwithstanding the expected nugget effect in a natural alluvial system), the results of the 14 bulk samples have been combined per placer mineral to give average recovered grades of these minerals as a first-pass estimation in this Zone (Table 1). The overall TMA grade was some 153 cpht (at a bottom screen size of 1 mm), with the grade dominated by 4 Gem Box suite minerals: spinel (69.91 cpht); Carmel sapphire™ (39.36 cpht); garnet (34.09 cpht) and ilmenite (12.06 cpht).
  • The spatial positioning of the bulk samples from south to north along much of the length of Zone 1, as well as their layout approx. perpendicular to palaeo-flow direction of the ancient Kishon in places, will allow for better geostatistical analyses of the grade and size distribution of the Gem Box and HIM industrial minerals in Zone 1 that will be presented at a later stage.

TARGET MINERAL ASSEMBLAGE SUITE & A REVISION OF THE GEM – INDUSTRIAL MINERALS COMPRISING THE TMA IN ZONE 1 OF THE KISHON MID REACH ALLUVIAL PLACER

The combined gem and industrial mineral component of the Kishon Mid Reach alluvial placer is referred to as the Target Mineral Assemblage. The “DMCH” gem suite made up of Diamond (extremely rare and mostly small, <1 mm stones; only one record from the Kishon Mid Reach alluvial placer from borehole SY-18), Moissanite (SiC, a rare mineral globally of which the Shefa Yamim prospects host the most abundant and the largest size natural moissanite in the world), Corundum gem varieties namely, Carmel sapphire™ (to date, a sapphire type known only from Mt Carmel and the Kishon Valley alluvial deposits), sapphire and ruby, and Hibonite (another rare gem).

However, with the last of the 14 bulk samples processed to completion by late April 2018, the combined total of 6,384 tonnes from Zone 1 yielded a large number of stones and carats per mineral species of the original TMA suite as defined above (5,825.24 carats, cts). This provided an opportunity to review the status of the original TMA, in particular the large garnet (2,176.77 cts) and ilmenite (768.86 cts) populations, as well as the most abundant potential gem mineral recovered to date, viz., spinel (3,952.91 cts). This investigation demonstrated that:

  • The garnet population, which is not of the more common metamorphic origin but was sourced from deeper levels by the Cretaceous Mt Carmel basic to ultra-basic volcanic complexes, is of a gemstone and not an industrial quality. These garnets, which also form an integral part of the so-called Kimberlitic Indicator Minerals (KIMs) suite, were tested further by cutting and polishing several stones, the results of which confirmed their gem quality. Therefore, the Kishon alluvial placer garnets are no longer considered part of the original HIM suite and have been re-assigned to Gem Box suite.
  • The ilmenite, which is also a KIMs mineral, but is generally finer-grained than the garnet, was likewise studied and found to be predominantly of a gemstone and not of an industrial quality. Therefore, the ilmenite population in the Kishon Mid Reach Placer has also been re-assigned to the Gem Box suite from the original HIM suite.
  • Significantly, and in addition to the original TMA suite (described above) that is the focus of the Shefa Yamim Recovery at the Akko facility, the Recovery personnel also pick spinel and other remaining KIMs (e.g. clinopyroxe, chromium diopsides, etc) as a matter of routine. Significantly the Zone 1 placer gravels yielded a considerable quantity of spinel, most of which was gem quality and relatively coarse-grained (3,952.91 cts). Thus spinel has been added as an additional mineral to the original TMA suite.
  • The TMA now comprises of 9 gemstones (in order of abundance): spinel, Carmel sapphire™, garnet, ilmenite, sapphire, hibonite, moissanite, ruby, diamond (not recovered in the Zone 1 bulk sample campaign and only known from borehole SY-18 in Zone 2); and 2 industrial minerals: zircon and rutile.

Information on historical bulk samples, as well as images and maps can be found on our website:
https://irp-cdn.multiscreensite.com/ac660adf/files/uploaded/SY_CPR_10_2017.pdf

Competent Person:

This release has been approved by Dr. J.D. Ward, Consulting Geologist at Majimba Geo-Consulting. Dr. Ward is a qualified geologist (Pr.Sci.Nat), and a leading alluvial diamond exploration geologist with over 35 years’ field experience.

Table 1: Summary of the carats (cts), grades (cpht; at bottom screen size of 1 mm) and two-fold size split for the revised TMA suite from the Zone 1 bulk sampling campaign which now comprises the Gem Box and the HIM suites. More info at this link

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