Properly Punctuated: Colon, :

Posted December 14, 2014 by Kathy Davie in Author Resources, Editing, Properly Punctuated, Self-Editing, Writing

A colon gives warning whether it’s to emphasize, distinguish between hours and minutes or volumes and pages or chapter and verse, introduce greater details, or join closely related clauses.

Punctuation is…

…the proper use of quotation marks, commas, semicolons, colons, ellipsis, etc., including how to properly mark dialog, ahem. As Properly Punctuated is in no way complete, I would appreciate suggestions and comments from anyone…

If you’d like to track it, bookmark this page — and consider sharing this Properly Punctuated tidbit with friends by tweeting it.

Colon, :
Credit to:; The Punctuation Guide
Punctuation:  :
Definition: A punctuation mark that notes a major division in a sentence, to indicate that what follows is an elaboration, summation, implication, etc., of what comes before; or to separate groups of numbers referring to different things.


Independent Clause(s)
Independent Clause + Detail Rule: Used after an independent clause, a.k.a., a complete sentence, to introduce a more detailed explanation, example, series, or statement.

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I have included books many people have read: The Da Vinci Code, for example.

We need warm clothing for the refugees: coats, mittens, scarves, hats, and boots.

Join Two Independent Clauses Rule: Between two independent clauses when the second explains or expands the first.

APA requires that you capitalize an independent clause following a colon.

Chicago requires it to be lowercase IF it is only ONE sentence. If there are two sentences which pertain to the reason for the colon, then capitalize both.

The key is to be consistent throughout the document.

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The leaders made the final decision: The earthquake victims would receive food and medical supplies.

The sign was all too clear: “Here there be dragons”.

Here is our honest opinion: We think you are a genius.

Create Emphasis with an Appositive Rule: After an independent clause, create emphasis by using a colon instead of a comma to introduce an appositive (word, phrase, or clause) at the end of a sentence.
CAUTION: Use lowercase if the word, phrase, or clause following the colon is not independent.

Begin the clause with a capital letter if it is a second independent clause.

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  1. Green indicates the colon and appositive word, phrase, or clause
  2. Blue indicates the colon and start of the independent clause

He was watching his favorite type of television show: a baseball game.

He learned a valuable lesson: Never argue with a woman.

The reaction of the audience signified one overwhelming feeling: fear.

List Rule: After an independent clause, use a colon before formally introducing a list.

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I’ll need the following ingredients:

  • flour
  • sugar
  • cashews
  • butter
  • vanilla

I need to run these errands:

  • bank
  • post office
  • grocery store
  • hardware
Bible Rule: Between chapter and verse.

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You will find those words in Genesis 1: 14-17.
Block Quote Rule: Introduce a block quotation.

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Per Hamlin’s own words on the topic:

“The hunt for the chemical responsible for this particular reaction encompasses a wide-range of disciplines including…”

Salutation in a Letter Rule: After the salutation in a formal letter.

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Dear Mr. Jones:
To Whom It May Concern:
Subject in a Letter Rule: After the introduction of the subject of a letter.

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Re: Blog post on colons

Subject: Holiday Lights on the Square

Attention: Accounts Payable

Abbreviations Used Rule: After an abbreviation to introduce the pertinent details or information.

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cc: Tom Smith
PS: Don’t forget your swimsuit.
Ratio Rule: Used to express a ratio of two numbers, with no space before or after the colon.

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1:2 = 3:6.
The ratio of 5 to 2 may be written 5:2 or 5/2.

The ratio of stars to triangles is 5:2.

Time Rule: Between hour and minute.

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At 4:01 p.m. the doors will be opened.

She said the train leaves at 8:07 p.m.

Separate Volume From Page Rule: Used to separate the volume from page numbers of a cited work, with no space before or after the colon.

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Punctuation Quarterly 4:86–89

Translates as volume 4, pages 86 through 89.