Question: Where do the Schwann cells and melanocytes originate from?

Context:
The development of the nervous system involves cells remaining within the neural tube (CNS) and a group of cells that delaminate from the dorsal neural tube and migrate extensively throughout the developing embryo called neural crest cells (NCC). These cells are a mesenchymal highly migratory group of cells that give rise to a wide variety of cell derivatives: melanocytes, sensory neurons, bone, Schwann cells, etc. 
Cell types with neural crest ancestry consequently comprise a number of specialized varieties, such as ectodermal neurons, melanocytes and Schwann cells, as well as mesodermal osteoblasts, adipocytes and smooth muscle cells. 
Melanocytes, the pigmented cells of the skin, and the glial Schwann cells lining peripheral nerves are developmentally derived from an early and transient ectodermal structure of the vertebrate embryo, the neural crest, which is also at the origin of multiple neural and non-neural cell types. 
Later, SoxE proteins drive the formation of multiple neural crest derivatives including chondrocytes, melanocytes, and cells of the peripheral nervous system, particularly Schwann cells/peripheral glia. 
Melanocytes and Schwann cells are derived from the multipotent population of neural crest cells.
The present results suggest that the induced hamster melanomas originate from neural crest-derived cells which are able to differentiate into both melanocytes and Schwann cells.
Melanocytes and Schwann cells both arise from the neural crest during development, and some melanocytes arise directly from Schwann cell precursors lining developing spinal nerves
Schwann cells, the myelinating glia of the peripheral nervous system (PNS), originate from multipotent neural crest cells that also give rise to other cells, including neurons, melanocytes, chondrocytes, and smooth muscle cells
In the vertebrate embryo, Schwann cells lining the peripheral nerves originate from the neural crest (NC), a structure that also gives rise to ganglion satellite cells, most of the neurons of the peripheral nervous system, melanocytes, and part of the cranial mesenchyme
The present results suggest that the induced hamster melanomas originate from neural crest-derived cells which are able to differentiate into both melanocytes and Schwann cells
Thus, the nevus cells shared a common nature with epidermal melanocytes and Schwann cells which originate from the neural crest; however, the former cells were somewhat different from the latter two kinds and from benign and malignant tumors derived from these cells in the expression of these antigenic substances
Melanocytes, the pigmented cells of the skin, and the glial Schwann cells lining peripheral nerves are developmentally derived from an early and transient ectodermal structure of the vertebrate embryo, the neural crest, which is also at the origin of multiple neural and non-neural cell types
Furthermore, although both populations are initially part of the Foxd3 lineage, hypaxial melanocytes lose Foxd3 at late stages upon separation from the nerve, whereas we recently found that epaxial melanocytes segregate earlier from Foxd3-positive neural progenitors while still residing in the dorsal neural tube. 
Reversal of developmental restrictions in neural crest lineages: transition from Schwann cells to glial-melanocytic precursors in vitro.
Schwann cells, the myelinating glia of the peripheral nervous system (PNS), originate from multipotent neural crest cells that also give rise to other cells, including neurons, melanocytes, chondrocytes, and smooth muscle cells.
In the vertebrate embryo, Schwann cells lining the peripheral nerves originate from the neural crest (NC), a structure that also gives rise to ganglion satellite cells, most of the neurons of the peripheral nervous system, melanocytes, and part of the cranial mesenchyme.
Thus, the nevus cells shared a common nature with epidermal melanocytes and Schwann cells which originate from the neural crest; however, the former cells were somewhat different from the latter two kinds and from benign and malignant tumors derived from these cells in the expression of these antigenic substances.
Other already committed cells are the angioblasts forming the endothelial lining of the blood vessels, the neural crest cells differentiating into melanocytes and Schwann cells, and the blood-derived cells like chrondro- or osteoclasts.
The dorsal neural tube first generates neural crest cells that exit the neural primordium following an epithelial-to-mesenchymal conversion to become sympathetic ganglia, Schwann cells, dorsal root sensory ganglia, and melanocytes of the skin.
We show here that neural crest cells arising from the neural tube located at the level of somites 47-53 can differentiate both in vitro and in vivo into melanocytes and Schwann cells but not into neurons.
This capacity may be due to the common origin of Schwann cells and melanocytes in the neural crest.
Melanocytes and Schwann cells both arise from the neural crest during development, and some melanocytes arise directly from Schwann cell precursors lining developing spinal nerves.
In the vertebrate embryo, multiple cell types originate from a common structure, the neural crest (NC), which forms at the dorsal tips of the neural epithelium.

Answer: Schwann cells and melanocytes originate from the multipotent population of neural crest cells.
Exact answer: neural crest cells, NCC