Just an update to this thread as I own a vase in the larger wider size as shown in Ivo's picture below.
Re Ivo's cased opalescent pieces then in two different sizes shown here:
https://www.glassmessages.com/index.php/topic,30223.msg163790.html#msg163790Both pieces are shown in the Czech Glass Revue CGR 68/10 where a full photograph of all the 5 pieces in the range is shown together in one photograph. However the wider bowl is not completely shown (cut off in the photograph) and the corresponding number isn't shown for it annoyingly.
The taller narrower piece of Ivo's two is actually a cigarette holder (Zigarettenstander) and is shown as number 54016 - by Oldřich Lpa as already noted.
With reference my most recent post reply#34 above quoted here, I've started a new thread about these vases as I also own one of the shapes. They are also by Oldřich Lpa and are shown in a set of 4 different shapes in one photograph also in the CGR 68/10. They are not by Koloman Moser:
http://www.ebay.ca/itm/181347702935
did we ever work out whether this was also Moser and Oldrich Lipa - maybe from a 'series' or something?
or this one which appears sometimes with grey blobs and sometimes with black blobs
https://www.botterweg.com/Moser_Koloman/Lot-21547.aspx?tabid=59&lotid=21547&language=en-US
This one sold for Eu.1100 in 2006 - it has a reference for Koloman Moser and Loetz but I don't have the reference to check.
https://www.liveauctioneers.com/item/2658506_koloman-moser-vase-um-1903
'Weite zylindrische Gefform, flach eingezogene Schulter, zylindrischer Hals, angeschmolzene, runde Standscheibe. H. 17,5 cm. Ausfhrung: Joh. Ltz Wwe., Klostermhle. Weies Opalglas, krftig farblos berfangen, zweifache Nuppenaufschmelzung sowie Stand aus schwarzviolettem Glas.
Vgl. Werner Fenz, Koloman Moser, Salzburg und Wien 1984, Farbtafel S. 81.'
Thanks for any help 
m