We have been able to aquire a limited about of vintage white heart glass spacer beads that are perfect for all sorts of projects that require a historically correct look. 

Available in a few select colors, and still strung on the original raffia cords, these are a great find. 
 
Please see below for approximate sizing and length 
 
Orange- 7.5 MM x 6.25 MM- 21 inches long 

Blue- 5MM x 6.25 MM- 21.5 inches long
 
Green- 5MM x 6 MM- 21 inches long
 
Red (Large)- 5.25MM x 6.25 MM- 22 inches long
 
Red (Small)- 5MM x 6 MM 20 inches long

These are vintage beads, strands and sizes are approximate and will vary from strand to strand.
 
History of White Hearts: 
White Heart Beads (also referred to as “Cornaline D’aleppo“, or “Hudson’s Bay Beads”) were a type of Venetian Trade Bead produced in Venice, Italy, between 1805 and 1900. While highly collectible, these two-tone beads are considerably plainer compared to other sought-after trade beads of the time, such as Millefiori Beads, with an off-white or light yellow core enveloped by a skin of scarlet, orange or dark red glass. Historical findings suggest the brilliant red of some White Heart Beads was achieved by adding gold oxide to the glass.
"White Heart" beads were invented around the year 1480, whereby red glass was colored using actual gold. Naturally, because of its value, the gold had to be used sparingly by the bead makers. As such, they instead opted to use inexpensive color filler for the core of the bead with the red only forming the outer layer. During the years 1480 – 1830, bead makers began using green color to craft these beads. However, after 1830 both yellow and white were commonly used, along with a translucent red coat. After 1860, bead makers stopped using yellow altogether in making White Heart beads and exclusively opted for white color.