See the tips given in "How to Read a Primary Source" in Patrick Rael, Reading, Writing, and Researching for History: A Guide for College Students (Brunswick, ME: Bowdoin College, 2004).
Archives, libraries, and museums continue to digitize and transcribe their collections of primary source materials and make them freely accessible online. Surrogates of original primary source materials may be considered equal substitutes for the originals; however, it is best to always evaluate a reproduction for credibility. For more information on determining the trustworthiness of primary source surrogates, see Lafayette College Library's Primary Sources: Evaluating.
Archival Silence: n. The unintentional or purposeful absence or distortion of documentation of enduring value, resulting in gaps and inabilities to represent the past accurately.
Dictionary of Archives Terminology, s.v. "Archival Silence," accessed September 17, 2021, https://dictionary.archivists.org/entry/archival-silence.html.