The JORC resource is in line with the historic resource estimate of 1.11Bt at 10.4% K2O containing 114.9Mt.
The Mühlhausen‐Keula resource grades 11.1% and comprises mostly sylvinite (834 million tonnes at 12.10% K2O) and carnallitite (295.8 million tonnes at 8.2% K2O), with significant amounts of sulphate‐rich and magnesium‐rich potash minerals.
These are becoming important for the production of multi‐nutrient fertilisers increasingly sought by customers, Davenport said.
The resource also contains exceptionally low levels of insoluble minerals, such as clays, which will facilitate metallurgical processing.
In April, the company released its first maiden JORC-compliant inferred potash resource covering the Ebeleben licence for 576.6 million tonnes at 12.1% K2O.
"This dramatic increase in our overall JORC inferred resources means we are well on the way to declaring Europe's largest potash resource," managing director Dr Chris Gilchrist said.
All told, Davenport now controls over 1.7Bt grading 11.4% K2O of JORC inferred resources from its Ebeleben and the Mühlhausen‐Nohra licences in a market where prices for the fertiliser have been above US$300 per tonne in north-western Europe, Southeast Asia and Brazil.
Once the Nohra‐Elende resource is tallied, Davenport is planning a targeted program to upgrade the resources to indicated status by carrying out confirmation and exploration drilling in selected areas.
The Mühlhausen‐Nohra resource calculations were based largely on drillholes dating back to the East Germany era when the area was explored during the 1960s and 1970s.
The resources cover just 13.5% of the 650sq.km under Davenport's control, which are contained within three perpetual mining licences in the South Harz Basin that Davenport acquired recently from the German government.
The Mühlhausen resource extends well into the Küllstedt licence, and ongoing work may lead to the definition of further JORC resources in the near future, the company said.
The South Harz Basin has produced more than 180Mt of potash, and was a major producer until the late 1980s, but developments ended following the German reunification.
Shares in the potash hopeful were untraded at A5c this morning, valuing the company at $7 million, however major shareholder Parkway Minerals saw a drop of 14%, with its shares plunging to 0.6c, rendering its market capitalisation a mere $3.7 million.
Parkway owns around 32% in Davenport.