| Municipal landfills MSW containing WEEE [17] | Estimated Ta concentration in MSW about 1 mg/kg which is lower than the average concentration of Ta (2.4 mg/kg) in earths crust. | In countries where the share of landfilling has been significant in 2000’s/Municipalities | Low concentrations mixed into large amounts of MSW. Very little information and no data about Ta concentration found. | Soiled small electronic devices or their components | Capacitors and other electronic components mixed in large amounts of MSW and materials used for daily cover |
| Disposal areas of incineration slags. MSW incinerations slags [2] | About 61 000 t/d slags produced in EU, most of the Ta in the incinerator feed ends up to bottom ash | EU countries/Municipalities, energy producers, etc. | Low concentrations, contains other metals, very little information from Europe | Mostly in > 2mm particles | Estimated 3–5 mg Ta/kg |
| Industrial landfills containing waste from WEEE processing [17] | Not applicable | In several EU countries/Recycling companies |
| Mostly crushed materials, particle sizes from very fine to over 10 cm, may contain also specimens that are not crushed | Not applicable |
| Mine waste [9] | Not available | Echassieres, France |
| Not applicable | Not applicable |
| Mine waste [10] | Closed pegmatite mine | Hagenforf, Germany |
| Not applicable | Not applicable |
| Tin mining residues tantalite Albite-, Amblygonite-, Arsenopyrite-, Beryl- Cassterite-, Columbite-, Muscovite-, Pyrite-, Quatrz [12] | Not known, surface storage areas | Vieiros Canadelo, Porto Region, Portugal | Closed tin mining area | Not applicable | Ta concentrations not available |
| Tailings and waste from tin mining [9] | Tailings 5Mt and waste dump 6.8 Mt | Penouta, Spain/Aprovecha mineto Mineiro | Closed tin mining area, tailings and waste studied for recovery of Ta | Not applicable | Tailings 48 g/t; waste dump 27 g/t |
| Mine waste and tailings [9] | Not known | Bessa, Portugal |
| Not applicable | not applicable |
| Slag [22] | About 1 000 t of radioactive slag from Nb production Larger amounts of light waste Apatite-Calcite-Mica, deposited to the sea | Sove, Norway | Small quantity, due to radioactivity will be either transported to a waste area or contained | Not applicable | Containing Ta (1.34% Ta2O5), Th, Zircon |
| Waste from uranium mining [12] | not applicable | Straz, Czech republic |
| Not applicable | Not applicable |
| Mine tailings, pegmatite-granite 12] | Cosed Be-Ta mine | Rosendal, Finland |
|
| Li-Nb-Ta |
| Tin slag [22] | Not know | Golbejas, Salamanca Spain | Tin and Ta mine closed in early 1980s, potential to start mining again has been studied. Waste areas have been at least partly reprocessed in 1980’s | Not applicable | Not applicable |
| Tailings of china clay extraction [18] | Ta, Nb, Ti, Sn Columbite-tantalite cassterite, Nb-Tarutile No info on concentration | St Austell, Cornwall | Gravity separation can be used for enrichment of Ta concentrate from fine grained waste | Fine particles | Several locations |
![Main applications of Ta [4]](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/6470700c83f1392090d69816/j_acee-2020-031_fig_001.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKBBM74A4T%2F20251213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20251213T002256Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEEcaDGV1LWNlbnRyYWwtMSJHMEUCIQCSDFPXoBx8KZl1JnEbdah40IdHkMYigz%2Fuc%2FSTS1xdfwIgKyEwuYwFB4fC1i%2FlmTTEeV11fS3x%2B3syRomnHgSkJ%2F8qvQUIEBACGgw5NjMxMzQyODk5NDAiDNmcanWJdL7QX77z4yqaBSVVZ4aykYGiy0gH2aOP3Vvu6kOj%2FY9imVDLOK8ljiYEmNB6169t3NT6AmkKHLmzu95NZzeI58EuHBHBEAEMNOXtHwS128qFT0ElRsj39%2Flbu013o0xhAgHztYBlfBCcb2Y%2BrwLuSIIjdKPtoFq%2B0UX5F%2BT4tqXjeASF7qIDNs7WcUVCZ7owirnrNIjh1aNIfUDdQtDyYkJQlHtPLB4rQzDvWOzhqhiygdo8s3o0jvTQSFjob3PtidqI6ackbtGUXjIhXWvEnc8kcGN8vLlNVJccx%2FgOr0jIRUnLvuIxFVTJ7vCopRxpGGpBOV%2Bpx3B7vWF8h%2F7tv1k%2B8QDKOhxS3gKHiXzlVCeiOueMuT1wBoAyvjilmaIN1PBsaqE1Ukyt8TfyloJgKrhI%2BXDARz%2ByoGnuT59w%2B5cUqv4WQejYkz%2FGUcU1yD%2BVnCe13sXk5dVnxGAP3GcasUkwZsikRFFM%2FZN1VT7boO2nuftzTD3ImVWqEZWDQk6huPs0PJYb6LqVxYdQ%2B3uYUyyjfGWOu4Epb%2B6Rz59U57yGThYWQYq8mY0dYsOeVxa0UWQhfJRvBbmfkzVJRpC175ICQtac4q%2FjCbLe4UaheFseaDorrweOMyqzaXpkp3Jk5CV0BpwIonj84rnSm7QgXbmZIYyeSTGRU2rHLxpzHKRX%2F387PDEhFcYqGTM%2Blvv6U3Y7WDDTBCViADcZFPX6Fdj7cX4lOIOa4n64lz6DtBl%2BlORVDIFPy%2Br4HHJfvASeEX19GMNHBDk6MwNK8s8vX52VSyIfJYZaYdveCaT0GgP2MY4cqqTEzNmesazW0iE9SwWmdx%2Fs24wC5Dj%2Bq1HDAM%2BRQ8HhxV9iMIy4MU55JtB%2FaonrCcTWlLCPNGIMXP9TV%2BYSmDCGsvLJBjqxAcUMnNCUuGRg7%2Bbmf9HGOeVkesZWhTtnsGfFwGd0F%2FPCb%2Bajq6RvD2FM1fM95bITTq6hCyIeU9Q1KmvP1bsZHeUQ5UozZABX%2FBEQxpUD0SLMwtY3RHpnF2xUNxDcfAHNnKC5CaENpOT83ddozoTkNR5gJab5RnzbpL4I5GRopi504YJ%2BwoXE8wBySmT%2BW8GO8A93Vny0JEe8IV6igkgdyjQVBDFUTKoK41%2F6iF0P51S00Q%3D%3D&X-Amz-Signature=ec6d2da39e0e5d10a53431fe74f9e90ea99ed0839c00c3156e02d5176ac2e60b&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)
![The areas of Penouta Mine [9]](https://sciendo-parsed.s3.eu-central-1.amazonaws.com/6470700c83f1392090d69816/j_acee-2020-031_fig_002.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=ASIA6AP2G7AKBBM74A4T%2F20251213%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Date=20251213T002256Z&X-Amz-Expires=3600&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEEcaDGV1LWNlbnRyYWwtMSJHMEUCIQCSDFPXoBx8KZl1JnEbdah40IdHkMYigz%2Fuc%2FSTS1xdfwIgKyEwuYwFB4fC1i%2FlmTTEeV11fS3x%2B3syRomnHgSkJ%2F8qvQUIEBACGgw5NjMxMzQyODk5NDAiDNmcanWJdL7QX77z4yqaBSVVZ4aykYGiy0gH2aOP3Vvu6kOj%2FY9imVDLOK8ljiYEmNB6169t3NT6AmkKHLmzu95NZzeI58EuHBHBEAEMNOXtHwS128qFT0ElRsj39%2Flbu013o0xhAgHztYBlfBCcb2Y%2BrwLuSIIjdKPtoFq%2B0UX5F%2BT4tqXjeASF7qIDNs7WcUVCZ7owirnrNIjh1aNIfUDdQtDyYkJQlHtPLB4rQzDvWOzhqhiygdo8s3o0jvTQSFjob3PtidqI6ackbtGUXjIhXWvEnc8kcGN8vLlNVJccx%2FgOr0jIRUnLvuIxFVTJ7vCopRxpGGpBOV%2Bpx3B7vWF8h%2F7tv1k%2B8QDKOhxS3gKHiXzlVCeiOueMuT1wBoAyvjilmaIN1PBsaqE1Ukyt8TfyloJgKrhI%2BXDARz%2ByoGnuT59w%2B5cUqv4WQejYkz%2FGUcU1yD%2BVnCe13sXk5dVnxGAP3GcasUkwZsikRFFM%2FZN1VT7boO2nuftzTD3ImVWqEZWDQk6huPs0PJYb6LqVxYdQ%2B3uYUyyjfGWOu4Epb%2B6Rz59U57yGThYWQYq8mY0dYsOeVxa0UWQhfJRvBbmfkzVJRpC175ICQtac4q%2FjCbLe4UaheFseaDorrweOMyqzaXpkp3Jk5CV0BpwIonj84rnSm7QgXbmZIYyeSTGRU2rHLxpzHKRX%2F387PDEhFcYqGTM%2Blvv6U3Y7WDDTBCViADcZFPX6Fdj7cX4lOIOa4n64lz6DtBl%2BlORVDIFPy%2Br4HHJfvASeEX19GMNHBDk6MwNK8s8vX52VSyIfJYZaYdveCaT0GgP2MY4cqqTEzNmesazW0iE9SwWmdx%2Fs24wC5Dj%2Bq1HDAM%2BRQ8HhxV9iMIy4MU55JtB%2FaonrCcTWlLCPNGIMXP9TV%2BYSmDCGsvLJBjqxAcUMnNCUuGRg7%2Bbmf9HGOeVkesZWhTtnsGfFwGd0F%2FPCb%2Bajq6RvD2FM1fM95bITTq6hCyIeU9Q1KmvP1bsZHeUQ5UozZABX%2FBEQxpUD0SLMwtY3RHpnF2xUNxDcfAHNnKC5CaENpOT83ddozoTkNR5gJab5RnzbpL4I5GRopi504YJ%2BwoXE8wBySmT%2BW8GO8A93Vny0JEe8IV6igkgdyjQVBDFUTKoK41%2F6iF0P51S00Q%3D%3D&X-Amz-Signature=8185235f93ced6a8778229d415e844a4ac645891cb35ae025088428f545a20fc&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)