Singing Sands of Sankumukam beach, Trivandrum, India.

Singing Sands of Sankumukam beach, Trivandrum, India.

Singing sands are known to exist in some beaches in different parts of the world. One example near home is the beach sands of Sankumukam, Trivandrum. In fact, the Sankumukam beach sand is near glass quality sand and its black sand component is noticed in the beach immediately to the north of Kovalam headland where the former ITDC hotel complex stands.

Now some points about the singing sands. What is this sand and why is it designated so? Unfortunately, the masonry construction in the backshore to erect a Broad walk, is an intrusion into the natural system. The SW monsoon wave erosion removes practically all the sand stored in the summer berm.

However, when the beach is rebuilt after the monsoon, with a distinct summer berm there is a wide backshore. If one walks over this beach bare footed, and kicking the sand under the feet with the heel an audible squeak is created due to rubbing of the sand by the heel. Such sands are described variously as booming or roaring sands.  In fact, this nature of the sand earned the name singing sand for the beach sand of our own town beach.

What is the source or what are the attributes of this sand that generates an audible squish? According to Sir C V Raman, (who took time out to walk this beach in the early 1950’s, when his flight was delayed by two hours or so and decided to check out this character of the sand in the Sankumukam beach), the moisture content, shape of the sand particles, size and degree of sorting as well as nearly uniform mineralogy, or pure quartz are contributing factors. Sir Raman made this comment to the young geologist, Mr. kVK Nair (then of the Division of Mineral Survey and Research Central Research Institute, the Travancore University) in the presence of Dr. CS Venketeswaran( then Principal, University College, Trivandrum). However, so far an instrumented study of this characteristic never came under scrutiny. The only attribution is that the Sankumukam sand qualifies for designating as glass quality or glass sand like the Chertala Glass sands deposits and makes the audible squeaking sound.

Similar sand occurrences have been reported from other parts of the world, like California and Nevada (dune sands), Kazhakastan, UAE,  Abu Dhabi etc).