[78-L] Lamination Cracks

[marimbamoods at comcast.net]

i recently acquired a copy of Paramount 30083, a blue label issue from 1918. it has a series of raised faults, maybe half a dozen or so, radiating outwards from the center hole to the edge that resemble frost heaves in paved roads. 


the grooved surface of the shellac itself is not broken, but it is raised along these heave-lines. it seems like an under-layer has created upheaves that are in the process of cracking the surface shellac, but that the process has not broken completely through to the top surface - it is only bending the top layer, not breaking/cracking it. 


i have not played/digitized this disc yet, but expect that - with the right sylus - it should play through ok, probably with ticks. 


does anyone know the composition of these 1918 Paramounts, i e, are they laminated and if so, laminated from what substances? can i expect this condition to deteriorate further over time? 


thanks in advance, 
david harvey