here my suggestions for calendar icons:
A lot of these exist already. Do you have examples of what these look like (that differ from the ones provided)?
You are the artist :)
Here I have a little inspiration. Hope it will help …
link
We already have blank calendar, calendar, day calendar, week calendar, task calendar.
maybe we can add them as aliases.
Thank you for your answer.
I'm working on an app where I need these icons as items in a menu bar.
calendar-blank is fine.
calendar or calendar-today as today's calendar also works.
A weekly calendar needs to recognize as a week calendar 5 or 7 dots not 3.
A monthly calendar needs to recognize as a month calendar 4 rows with 7 dots each row. (That would be imho that standard calendar. May be interpretable …)
A task or activities calendar means a place where you store places, times and tasks. That should the symbol show.
We cannot have that many dots per Google Material Design Standards.
Thank you for the efforts, but that doesn't fit my intention
Here is an variant for calendar-week.

Also, I believe that calendar-favorite would work for task/activity found here. Remember that this issue is still open and hasn't been added to the repo yet.

Sorry for the moment. I have to think about it :|
Google Calendar app:

Microsoft Outlook app (Calendar):


Which one of these is self explanatory without the label?
I believe Google Calendar is far too abstract and that Outlook did a good job. But honestly, what's wrong with the ones that I provided?
I agree with you
… that Outlook did a good job …
You are doing a great job with providing all these icons. Most of them I find best, uncontradicted. But in this way it doesn't fit my requirements. Thank you.
@KlausEichinger, we will close this issue once the aliases and the other new icons are added.
@Templarian can we add the above-mentioned aliases as well as the new ones I've created. I believe that they will add more variety to the calendar choices.
view-streamview-dayview-column (alternatively, view-week)view-moduleAliases added.
A slightly better centered version of calendar-favorite is available over here: https://github.com/Templarian/MaterialDesign/issues/1641#issuecomment-381342163
First day of week (Sunday/Monday): calendar-week-begin.zip

Calendar alert: calendar-alert.zip
