| 22. | Finance income and costs |
| $000 | | Year ended Dec 31, 2017 | | Year ended Dec 31, 2016 | | Year ended Dec 31, 2015 | | |||
| Finance income – interest income | | | 5,432 | | | 1,553 | | | 112 | |
| Finance income – net foreign exchange gain on financing activities | | | 586 | | | - | | | - | |
| Finance income | | | 6,018 | | | 1,553 | | | 112 | |
| Interest expense – borrowings | | | (1,721) | | | (1,724) | | | (1,147) | |
| Finance costs – net foreign exchange loss on financing activities | | | - | | | (399) | | | (1,867) | |
| Unwind of discount on provisions for environmental rehabilitation | | | (1,386) | | | (1,070) | | | (1,397) | |
| Finance costs | | | (3,107) | | | (3,193) | | | (4,411) | |
| Finance income/(costs) – net | | | 2,911 | | | (1,640) | | | (4,299) | |
| Interest income arises on cash and cash equivalents. | | | | | | | | | | |
| Interest expenses arise on borrowings measured at amortized cost. | | | | | | | | | | |