(Adds stability certifications, share move, context)
BRASILIA, April 1 (Reuters) - Brazilian miner Vale SA said on Monday it failed to obtain stability certificates for 13 dams under review following the rupture of another dam in January that killed hundreds, although its shares rose on strong global iron ore prices.
The world's largest iron ore miner also disclosed in a securities filing on Monday that a court had frozen an additional 1 billion reais ($258.42 million) in assets over potential damages related to the evacuation of its Vargem Grande dam.
Despite the disclosures, Vale shares jumped to their highest point since the Jan. 25 disaster, rising 3.6 percent to 52.79 reais.
Iron ore future contracts for May delivery rose as much as 5.2 percent on Dalian Commodity Exchange to hit a seven-week high on Monday, on strong economic data from China and supply concerns after Rio Tinto cut its 2019 forecast for iron ore shipments.
Vale said neither the lack of certificates nor the asset freeze would affect its iron ore and pellet sales forecast announced last week.
Courts now have frozen a total of 17.6 billion reais in Vale assets since the Jan. 25 disaster when a tailings dam burst at a Vale iron ore mine in the town of Brumadinho, in southeastern Minas Gerais state, burying hundreds of people in mining waste.
In response to the disaster, Vale and the Brazilian government are reviewing the safety of all of the miner's dams.
The miner disclosed that although 80 structures had their stability certificates renewed, another 13 dams and four dikes did not receive certifications.
Seven of them are so-called upstream tailings dams, the same type as the one that ruptured in Brumadinho. The areas around those dams already have been evacuated as a preventative safety measure.
The lack of safety certifications for the other structures will not require further evacuations, although they remain at higher states of alert under an official system that rates the risks of rupture.
Vale has said it has taken all upstream tailings dams offline as a precaution until they can be decomissioned, which could require them to reduce their output by up to 10 percent.
Last week Vale slashed its 2019 iron ore sales forecast by up to 20 percent to 75 million tonnes. Vale Chief Financial Officer Luciano Siani told analysts that safety and not boosting production remains the company's priority. (Reporting by Jake Spring and Jose Roberto Gomes Editing by Bill Trott)