From the file system, determined from the filename or from the registry.
System.ComputerName = uses the path to build the computer name (local computer name / remote computer name for \\server\share or mapped network drive)
System.ContentType = uses the extension to get the content type from the registry.
System.DateAccessed = File system.
System.DateCreated = File system.
System.DateImported = ? looks like this is using System.DateCreated.
System.DateModified = File system.
System.Document.DateCreated = Microsoft Office files store this property, looks like it falls back to System.DateCreated.
System.Document.DateSaved = Microsoft Office files store this property, looks like it falls back to System.DateModified.
System.FileAttributes = File system.
System.FileAttributesDisplay = Rendered from System.FileAttributes.
System.FileExtension = built from filename.
System.FileName = File system.
System.FileOwner = File system.
System.FilePlaceholderStatus = File system. (System.FileAttributes)
System.IsFolder = File system.
System.IsShared = From the Registry.
System.ItemDate = ? looks like this is using System.DateModified
Core properties:
https://learn.microsoft.com/en-us/windows/win32/properties/core-bumper