Dear Trenden:

I asked this question a long time ago on another listserv and absolutely
did not come up with a standard (so if someone has one, I'd love to hear
about it!). So, I made my own:

10th Century BCE = 1000-901 BCE
9th Century BCE = 900-801 BCE
.
.
.
1st Century BCE = 100-1 BCE

1st Century CE = 1-100 CE
2nd Century CE = 101-200 CE
.
.
.
12th Century CE = 1101-1200 CE
13th Century CE = 1201-1300 CE
etc.

Objects dated after 1000 CE to 1600 CE ---- ca. 1200 = 1000 - 1400
(range buffer of 200 years, CE designation drops)

Objects dated between 1600 to 1800 ---- ca. 1750 = 1650 - 1850 (range
buffer of 100 years)

Objects dated between 1800-1950 ---- ca. 1850 = 1825 - 1875 (range
buffer of 25 years)

Objects dated after 1950 to the present ---- ca. 1980 = 1975-1985 (range
buffer of 5 years)

ca. 1980's = 1980-1989

early 20th Century = 1901-1950

mid 20th Century = 1925-1975

late 20th Century = 1950-2000

Hope this helps!

Perian Sully
Collection Information and New Media Coordinator
Judah L. Magnes Museum


-----Original Message-----
From: Museum discussion list [mailto:[log in to unmask]] On
Behalf Of Treden Wagoner
Sent: Thursday, August 07, 2008 10:45 AM
To: [log in to unmask]
Subject: [MUSEUM-L] Guideline/Standards for Circa Dates?

Hello all,

I am curious what your museum uses as guidelines or standards for dates
circa? 

Do you use a standard deviation for all circa dates (plus or minus 10
years for example) or does the deviation change depending on how recent
the dates are (20th century is plus or minus 5 years, 19th century plus
or minus 10 years, etc.) 
This deviation would then be used to create begin and end dates for an
object. For example we might enter into our collections management
database for an object that is c. 1810 a start date of 1805 and an end
date of 1815. 

What do you use? Is there a national or international standard? Can you
point me to some reference material on the subject? I have done some
internet research and asked around here. Now I want to see what the
field says on the topic.

Thanks,

Treden Wagoner



Treden Wagoner
Coordinator of Education Technology Programs
The Minneapolis Institute of Arts
2400 Third Avenue South
Minneapolis, Minnesota 55404
612-870-3189
Toll free 888-642-2787 extension 3189
Fax 612-870-3004
Email [log in to unmask]
http://www.artsMIA.org
http://www.ArtsConnectEd.org

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