Frequently Asked Questions

• What are Rare Earth Elements?

  Rare earth elements (REE) consist of lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd),
  promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy),
  holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu). Yttrium (Y) is also typically
  grouped with the REE.

  TREO

  TREO are the total rare earth element oxides in the sample, with the REE metals expressed as rare earth element oxides, which is a common method for summarising the total grade.

  TREO-CeO2
  This is TREO minus the amount of cerium oxide in the sample. CeO2 is relatively low in value.

  PPM
  Ppm is parts per million by mass, which is the standard unit for reporting REE grades. 10,000ppm =
  1.0%.

  Permanent magnets
  Permanent magnets are used in electronic and computing equipment, batteries, electric vehicles, wind
  turbines, mobile phones and military systems. Nd & Pr are used in high-power permanent magnets. Dy, Sm and Tb are used in high-temperature permanent magnets. Some reporters called them “Super Magnet” REE.

  Ionic adsorption clay (IAC) rare earth elements
  In contrast with hard-rock REE ores, ionic adsorption clay REE mineralisation forms when REE attach loosely to clays and can be recovered by low-cost leaching methods.

  IAC REE deposits have been mined in southern China and Myanmar. ABx is one of the very few listed
  companies to discover true IAC REE mineralisation in Australia.

  Extraction rates from desorption tests

  To assess the potential of extracting REEs from prospects, tests have been carried out by ANSTO, who have extensive experience in metallurgical testing of clayhosted rare earth deposits worldwide. These were conducted at “standard” desorption conditions of 0.5 M ammonium sulfate at pH 4 which are low-acid, low-cost processing conditions for ionic adsorption clay REE.

  The ”extraction rate” is the proportion of REE contained in the sample that is extracted and reports to the leach solution. Very few other REE occurrences in Australia have achieved extraction rates that have been achieved on ABx’s REE mineralisation in the channels at the Deep Leads project area in northern Tasmania.

• What is Bauxite?

  Bauxite is a mainly a mixture of iron and aluminium hydroxides and oxides of Al, Fe, O and OH. Principal aluminium hydroxide minerals found in varying proportions are gibbsite and the polymorphs of boehmite and diaspore. Other components include SiO2, TiO2 and P2O5. The overall chemistry of bauxite determines its commercial usage.
  
  Gibbsite has the chemical formula Al (OH)3, which is a trihydrate. Boehmite and diaspore have the formula AlO(OH), which is monohydrate. The main mineral of aluminium in our bauxite deposits is gibbsite. Large bauxite deposits in China and Vietnam are either low grade, high in monohydrate minerals, and/or high in reactive silica. Dissolution of monohydrate minerals requires higher temperatures and higher concentration of caustic soda; energy consumption is much higher than for dissolution of trihydrate gibbsite.
  
  Dissolution of gibbsite requires lower temperatures and lower concentration of caustic soda, providing ABx with a significant competitive advantage.
  
  Moreover, our bauxite deposits have low levels of reactive silica and high total alumina to silica ratios. Reactive silica is the most harmful contaminant because it forms insoluble double Al, Na silicate which reports to red mud during conversion to alumina.
  
  High levels of reactive silica causes the loss of alumina and caustic soda, while TiO2 and P2O5 robs sodium. Our bauxite deposits are low in contaminants.