Colluli Resource

The mineral resource contains 1.289Bt of potassium bearing salts. 97% of the salts sit within Measured and Indicated categories. The Colluli deposit comprises:

  • Measured mineral resource: 303Mt at 10.98% K2O
  • Indicated mineral resource: 951Mt at 10.89% K2O
  • Inferred mineral resource: 35Mt at 10.28% K2O

The resource contains a K2SO4 equivalent of 260Mt (100% recovery basis), making it one of the largest potassium sulphate deposits in the world.

The Colluli JORC 2012 compliant resource is shown in the table below.

 

Area Rock Unit Measured Indicated Inferred Total
Mt K2O Equiv. % Mt K2O Equiv. % Mt K2O Equiv. % Mt K2O Equiv. %
Area A SylviniteCarnallitite

Kainitite

6655

86

127

12

38190

199

119

11

106

1

816

10

115251

285

119

11

Area B SylviniteCarnallitite

Kainitite

2425

48

156

13

122114

289

137

13

58

4

127

13

150147

341

137

13

Total SylviniteCarnallitite

Kainitite

9080

133

137

12

160303

488

138

12

1515

5

911

12

265398

626

128

12

            1289  

The Colluli resource comprises three potassium bearing salts. All are suitable for the production of potash fertiliser. The three salts are:

  1. Sylvinite– sylvinite is the most commonly used mineral for the production of potassium chloride. Potassium chloride, also known as Muriate of potash or MOP, is primarily produced from evaporite deposits in Canada, Russia and Belarus. These deposits are quite deep, with depths of over 1000m in Canada and to 300 to 500m in Eastern Europe. These deposits are typically mined using conventional underground mining methods, however, conventional mining is not suitable at depths deeper than 1,200m. Solution mining involves injecting heated solution into the resource, dissolving the valuable salts and pumping them to surface for subsequent processing. Sylvinite is a combination of two salts; sylvite (KCl) and halite (NaCl). Processing sylvinite is relatively simple.  The mined material is crushed to a size where sufficient liberation of potassium chloride and halite particles occur. The liberated materials are then selectively separated in flotation units. Halite is typically transported to a tailings storage facility and sylvite is dried and sold as potassium chloride (Muriate of Potash) fertiliser.

 

  1. Carnallitite– carnallitite is the combination of carnallite and halite. Carnallite rich brines are currently recovered from the Dead Sea to produce potassium chloride (MOP). Carnallite is a hydrated potassium magnesium chloride with formula KMg.Cl3.6(H2O). Carnallite occurs with a sequence of potassium and magnesium evaporite minerals; sylvite, kainite, Polyhalite and kieserite. Carnallite is an uncommon double chloride mineral that only forms under specific environmental conditions in an evaporating sea or sedimentary basin. It is mined for both potassium and magnesium and occurs in the evaporite deposits of Carlsbad, New Mexico, Utah, United States, and the Williston Basin in Saskatchewan, Canada. Israel and Jordon produce potash from the Dead Sea by using evaporation pans to concentrate the brine until carnallite precipitates. The carnallite is dredged form the pans and processed to remove the magnesium chloride from the potassium chloride.

 

  1. Kainitite– kainitite is the combination of kainite and halite. Kainite consists of potassium chloride and magnesium sulphate. Kainite exists in salt form in appreciable amounts in only three regions of the world; the Dallol Basin, Ukraine and Italy. Kainite was essentially depleted from the German Strassfurt mines with the salt being primarily used as a direct application fertiliser. With cessation of kainite mining in both the Ukraine and Italy, the Dallol Basin remains the last unexploited major deposit with kainite in solid form. Kainite is the key salt used for low temperature, high potassium yield production of potassium sulphate. It decomposes to an intermediate salt known as schoenite, and then reacts with potassium chloride under ambient conditions to produce potassium sulphate. In key potassium sulphate producing operations, Kainite is formed by evaporation of kainite rich brines. This increases footprint size and renders production rates subject to ambient conditions. Kainite can produce potassium sulphate or potassium chloride depending on the production process chosen. Kainite makes up over 60% of the Colluli resource and is seen as the key differentiating mineral species. The shallow mineralisation makes it easily extractable. Kainite is difficult to solution mine due to its solubility.