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Treat the files that you export as very sensitive data. You are exporting both your public and private keys. If someone else has access to your private keys, they can attach your electronic signature or encrypt files with your informationimpersonate you or read your encrypted emails.
In the Finder, open Utilities
Open Keychain Access.
Select your signing and encryption certificates from the list of displayed keychain items.
From the File menu, select Export.
Enter the name of the file you are exporting and select the P12 format.
Choose the location and filename destination where you want to export your certificate and click Next.
When prompted, create a password for the certificate files.
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