VALE Vale SA

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United States

Securities and Exchange Commission

Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16

of the

Securities Exchange Act of 1934

For the month of

December 2017

Vale S.A.

Avenida das Américas, No. 700 — Bloco 8, Sala 218
22640-100 Rio de Janeiro, RJ, Brazil

(Address of principal executive office)

(Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.)

(Check One) Form 20-F x Form 40-F o

(Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1))

(Check One) Yes   o No   x

(Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7))

(Check One) Yes o No   x

(Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.)

(Check One) Yes o No x

(If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b). 82-   .)

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Vale informs about short-term facilities to Samarco

Rio de Janeiro, December 21 st , 2017 — Vale S.A. (Vale) informs that it intends to make available short- term facilities of up to US$ 48 million to Samarco to support its operations (US$ 42 million) in the first half of 2018 (1H18) and the expenses related to the experts named pursuant to the Preliminary Agreement with the Public Prosecutors (about US$ 6 million), signed in January, 2017, without undertaking an obligation from Vale to Samarco. Funds will be released on an as-needed basis. Likewise, BHP Billiton Brasil Ltda. intends to make available to Samarco short-term facilities with similar terms and conditions as mentioned above.

In addition, given Samarco’s current cash flow projections, it is likely that shareholders will be called upon to fulfill its obligations, according to their stake in Samarco (50% each), under the Agreement signed on the March 2 nd , 2016 for the restoration of the environment and communities affected by the Samarco dam failure.  Therefore, Vale expects to contribute about R$ 432 million in 1H18, with this amount offsetting the R$ 3.7 billion provision recorded in the second quarter of 2016 (2Q16).

For further information, please contact:

+55-21-3485-3900

Andre Figueiredo: andre.figueiredo@vale.com

Andre Werner: andre.werner@vale.com

Carla Albano Miller: carla.albano@vale.com

Fernando Mascarenhas: fernando.mascarenhas@vale.com

Andrea Gutman: andrea.gutman@vale.com

Bruno Siqueira: bruno.siqueira@vale.com

Claudia Rodrigues: claudia.rodrigues@vale.com

Denise Caruncho: denise.caruncho@vale.com

Mariano Szachtman: mariano.szachtman@vale.com

Renata Capanema: renata.capanema@vale.com

This press release may include statements that present Vale’s expectations about future events or results. All statements, when based upon expectations about the future, involve various risks and uncertainties. Vale cannot guarantee that such statements will prove correct. These risks and uncertainties include factors related to the following: (a) the countries where we operate, especially Brazil and Canada; (b) the global economy; (c) the capital markets; (d) the mining and metals prices and their dependence on global industrial production, which is cyclical by nature; and (e) global competition in the markets in which Vale operates. To obtain further information on factors that may lead to results different from those forecast by Vale, please consult the reports Vale files with the U.S. Securities and Exchange Commission (SEC), the Brazilian Comissão de Valores Mobiliários (CVM), and the French Autorité des Marchés Financiers (AMF), and in particular the factors discussed under “Forward-Looking Statements” and “Risk Factors” in Vale’s annual report on Form 20-F.

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